How to select an uninterruptible power supply (ups) for your computer

How to select an uninterruptible power supply (ups) for your computer

What is an Uninterruptible Power Supply (UPS)?

Need help choosing a UPS Battery Backup?

Why do you need a UPS in your home or business?

How to select an uninterruptible power supply (ups) for your computer

Home: The electronic devices you rely on every day for communication, security and entertainment are at risk for damage and failure due to unexpected blackouts, voltage fluctuations or other power disruptions. A UPS provides battery backup power and protection for electronic devices, including:

  • Wireless networking equipment (routers, modems)
  • Computers
  • Televisions
  • Security systems
  • Gaming consoles
  • Mobile devices

How to select an uninterruptible power supply (ups) for your computer

Business: Downtime caused by power outages is frustrating for anyone, but can be financially crippling for a business or organization. Every year, billions of dollars are lost due to downtime caused by power disruptions that could have been prevented by a UPS. For Fortune 1000 companies:

  • Average annual cost of unplanned downtime, $1.25—$2.5 billion
  • Average hourly cost of infrastructure failure: $100,000
  • Average hourly cost of critical application failure: $500,000—$1 million

Small to medium-sized businesses may be at most financial risk due to a limited ability to generate revenue during downtime.

Local power quality and what gear you’ve got drive the desktop UPS decision

by Daniel P. Dern – A (good) surge protector can protect electronic devices that can tolerate losing power, whether for a fraction of a second, or a few hours, like printers, scanners, or a television. (Unless it’s being used for something that you can’t afford to have be stopped or interrupted.)

But to ensure your computer, external hard drive/file server/media center, cable box/DTR, router, answering machine and other devices not only are protected but also don’t stop, you need an Uninterruptible Power Supply (UPS).

UPSs fall into the same categories as backups: 1) things that desktop computer users need, and 2) things that are far easier and less expensive to get ahead of time than to discover you should have. For desktop/SOHO users, UPSs are available for anywhere from $50 to $200. Because getting the wrong one may be as bad as not having one at all, here are 5 tips for selecting a desktop UPS.


One of the two ways that UPSs are sized is the amount of power they deliver, usually stated in Volt-Amps (VA).

If the computer, monitor and whatever else you plug into the UPS’ Battery Backup outlets call for more power than the UPS can deliver, the UPS won’t work when there’s no power; they’re not set to prioritize based on outlet or whatever.

A good UPS will sense that you’ve plugged in more stuff than it can provide backup power for, and fail or alert instantly to let you know you’ve plugged too much in. But some won’t, so be sure to try it out, with everything powered up, but no unsaved files open, by removing the UPS plug from the wall, and see what happens.

Higher-power UPSs cost more than lower-power ones, so you need to strike a balance between power and price. Also, vendors can calculate how much power a device uses in different ways, so you can’t simply add device power numbers up. Plus, some devices draw more when starting up, or in heavy use.


How long will the UPS supply power?

That UPS battery isn’t a Green Lantern Corps Power Ring that’s good for 24 hours. Desktop UPSs are typically good for five to twenty minutes of power, depending on how big the battery is, and how much/little stuff you’re powering.

You should be looking for enough power to weather a brief outage, and let you close out your applications in a calm, orderly fashion. If you want to keep going when the power’s out for longer, you’re best off with a notebook computer — keeping in mind that the UPS may not power your broadband/WiFI for more than an hour or two.


How does the UPS decide when to spring into action?

In terms of how UPSs work, there are three main “topologies,’ in increasing order of tolerance for power problems (and in price):

STANDBY – Here, the battery power is used only when the voltage drops below a certain level, like below 90 volts (or completely goes away). This is the least expensive type of UPS, it’s what most people get.

strong>ON-LINE INTERACTIVE – This type of UPS has a transformer, so if the AC voltage gets too low (or too high), it brings it back within a target range, and only “goes to battery” when the incoming voltage drops too low or goes away. Get this if the power where you are is somewhat flakey; “going to battery” frequently is bad for the battery, reducing its capacity and usable lifetime.

strong>DUAL-CONVERSION, a.k.a. ON-LINE – Here, the UPS is always taking the AC power, turning it into DC and then back into AC. Get this if the power where you are has lots of interruptions, sags or micro-outages. or if you have equipment that needs sine-wave-like power (per below)


What the UPS power output looks like

If you look at the alternating current from your wall outlet on an oscilloscope, the power level looks like a sine wave.

The UPS battery is putting out direct current and the UPS’ circuitry is turning that into alternating current. The least expensive UPSs are simply burping out “square wave” A/C), slightly more expensive UPSs are putting out A/C that looks like stair steps, and the most expensive ones put out A/C that’s a sine wave looking the wall current or close to it.

Many devices can use the cheap square-wave power just fine. For example, your computer and monitor, which have power supplies, probably can. But many devices can’t, like some wireless routers; they won’t work right, might not work at all, or might even be damaged. So you need to do a little research (or testing).

Dual-conversion UPSs cost more, but the difference in cost will be a lot less than not being able to work, losing work in progress, or damaging your equipment.


All UPSs have outlets providing battery backup power, meaning that when there’s a power problem, these outlets will still push out power. These outlets are where you plug in your computer, primary monitor, cable/router box, external hard drives. the gear that you want to keep running when the power blinks or goes out.

Some also have “surge only” outlets that provide whatever protection the UPS has against surges, spikes, and noise, but not against dips, brownouts or outages. Plug printers, scanners, and other gear that you don’t mind stopping when the power goes out into these outlets.

Some UPSs also have Ethernet, cable and/or phone jacks, letting you also protect these lines against surges and spikes.

A plain old standby-type UPS with enough power may be good enough for you — unless your utility power is somewhat flakey, or your cablemodem and router need better power.

Daniel P. Dern is a freelance technology writer based in Newton Center, MA. His web site is and his technology blog is

This story, “Choosing a desktop Uninterruptible Power Supply (UPS)” was originally published by ITworld .

On its face value, a UPS battery backup power system is one that offers power facilities for a sustained period of time, long enough for a piece of equipment or device to safely shut down in case the main power system collapses. It helps to prevent loss of valuable data and work and at the same time, reduces the pressure a hard shutdown can cause on electrical equipment. A UPS carries out functions similar to a surge protector. It protects connected devices from power issues caused by surges or irregular voltages, which can shorten their lifespan and performance. While choosing a back-UPS for any residential system, it is critical to keep the following points in mind.

Number of Outlets

A UPS comes with multiple outlets. That is why it is important to define the number of devices that need to be connected to it. For homes or small offices, the devices that mandate the need for UPS connections are commonly a router, modem, and occasionally a mini server. Conversely, for larger businesses that require an industrial UPS, the necessity for electric support will be significantly higher. As a general consensus, it is a safe idea to choose a system which has a number of outlets which is greater than the actual requirement, as that provides emergency support as well.

Amount of Power Required by Appliances Connected

If devices require more power than the UPS can generate, then devices would not be able to operate, regardless of the battery having a substantial amount of energy remaining. It is comparable to a computer’s power management system. If the wattage is lower than what the computer needs, it is a problem.

Battery Running Time

While it is important to evaluate the amount of power required, it is equally imperative to examine the amount of time a user expects his or her UPS to operate during a blackout or power failure. Some users only need back-UPS for just a few minutes, to save some critical work and then effectively shut down the system without any risk of damage. On the other hand, some users require the system to operate during a period of power outage. That is why it is important for a user to understand their own requirements before installing a back UPS.


There is a wide range of back-UPS options to choose from, all of which offer unique features. Even the most standard consumer-level models provide features such as disconnecting battery notifications, USB connectivity, and a software suite that can be administered via computer to personalise settings while viewing power usage.


A UPS in typical conditions has a lifespan identical to that of its internal battery, which can last for two to three years. Batteries normally degenerate over time, especially when they are fully charged. UPS batteries—in their default state—remain charged all the time. Probably, all warranties are around the three-year mark—an ideal time period to cover the lifespan of the battery. However, in a few cases, some UPSs offer insurance above 3-year warranty.

Homes, small offices, or large-scale organisations, reliable and efficient back-UPS or smart UPS is a significant aspect that one should look for. There are multiple electrical management brands like #SchneiderElectric that offers products in this domain.

How to choose an uninterruptible power supply (UPS). An overview of capacity, output type, run time, and monitoring that can be used with any manufacturer.

There are many factors to consider when selecting an uninterruptible power supply (UPS). The basics are:

1. Capacity – How Much Of A Load Can I Place On A Battery Backup Uninterruptible Power Supply (UPS) Before It Doesn’t Work?

For example, if the device you would like backup power for has a label that says the input power is 120 volts, 3 amps, multiply 120 volts by 3 amps to get the wattage (360 watts). Then try to find a battery backup UPS with a capacity rating of at least 20% more than your device’s wattage. In this case, 360 watts multiplied by 1.20 (360 watts times itself plus 20%) equals 432 watts.

If we look at the passive backup power systems available, we have a 360 watt battery backup UPS and a 900 watt battery backup UPS which are the 2 models closest to our wattage load. We can’t use the 360 watt battery backup UPS to backup this electronic device, because it will most likely overload the 360 watt battery backup UPS. Instead, we select the model with the capacity rating over our 432 watt figure. In this case, it would be the 900 watt model.

2. Output – What Are All These NEMA This And NEMA That References?

NEMA stands for National Electrical Manufacturer Association. It is a standard used to ensure quality, format, and features are consistent between products in electrical distribution, lighting, enclosures, etc. There are many of these, so we will cover the one that is used most commonly.

The standard wall receptacle in the U.S. is a NEMA 5-15R (the R means receptacle). Anything that has a plug that fits in a standard wall outlet has a NEMA 5-15P (the P means plug). If your battery backup UPS says it has NEMA 5-15P (plug) input and NEMA 5-15R (receptacle) output, then you can plug it into a standard wall outlet for power and plug anything that uses a standard wall plug into the back of it for automatic backup power. Let’s break down the meaning below.

NEMA = National Electrical Manufacturer Association

5 = The voltage and format rating for this receptacle/plug. In this case the 5 means the outlet is meant for electronics that are powered by three wires (hot, neutral, and ground) that run at 125 volts maximum (110, 115, and 120 volt devices are typical and all use this receptacle/plug).

15 = The maximum amperage rating of the breaker typically associated with this outlet/plug.

R/P = R stands for receptacle and P stands for plug.

3. Battery Backup Time – How Long Will The Uninterruptible Power Supply (UPS) Run When The Power Goes Out?

A lot of people are confused by this and think that the capacity rating of the battery backup UPS (for example 1 kVA / 700 Watt) determines the amount of battery backup power time they will have during an outage. IT DOES NOT. This rating is used to determine the maximum load that can be put on a battery backup UPS. In this case, the maximum load of the UPS is 700 watts. Yes, if you use 100 watts instead of 700 watts, the battery(ies) will last longer.

The main determining factor of battery backup time is the NUMBER OF BATTERIES. There are a variety of other factors that impact the backup time like the amp hour rating of each battery, the voltage of each battery, the power factor of the inverter inside the battery backup UPS, etc., but the main thing to do to extend the battery backup time is to add batteries. You can do this by adding external battery packs to the main battery backup UPS which already has a set number of internal batteries. All of our online (double conversion) battery backup UPS models allow you to select and purchase additional external battery packs.

4. Monitoring – Do I Need All These Fancy Lights And Displays?

In most cases, all you will need to know is the current load level and how much backup time is remaining. In basic models, simple LED lights show the amount of battery remaining and the current load level the battery backup UPS is supporting. This will assist you in determining how much time you have to safely shut down the attached equipment before emergency backup battery power is depleted on the battery backup UPS.

If you want to monitor things like input/output frequency, input power load in VA/Watts, output power in VA/Watts, exact remaining backup power time in minutes, etc., high end battery backup UPS systems typically have these available on the front LCD screen. Our online (double conversion) battery backup UPS have a complete set of real-time statistics that can be viewed from the front LCD using the enter button to cycle through.

For personalized assistance in finding the right battery backup UPS for your need, please contact us by chat (bottom right corner), email ([email protected]), or phone (855-330-7799).

Protect your Windows or Mac computer from power surges and outages

Tom Nelson is an engineer, programmer, network manager, and computer network and systems designer who has written for Other World Computing,and others. Tom is also president of Coyote Moon, Inc., a Macintosh and Windows consulting firm.

  • Tweet
  • Share
  • Email

A UPS (Uninterruptable Power Supply), also called a backup battery, is a wise investment for any Mac or PC user. Even if you use software to back up your files, a UPS can be a lifesaver if you unexpectedly lose power. Before you pick a UPS battery backup for your Mac or PC, determine the size necessary to run your equipment when the power goes out.

Information in this article applies broadly to a range of devices. Check the specifications of individual products before making a purchase.

What Is a UPS for Computers?

There are different types of UPS systems. The type used with computers is a Standby UPS. It contains a battery that kicks in when the UPS senses a loss of power. The UPS sits between the power supply and the equipment it protects. It plugs into the wall outlet, and the devices plug into the UPS. A standby UPS for computer equipment provides two primary services:

  • Conditions the AC voltage to reduce power surges that can disrupt or damage a computer system.
  • Provides a computer with temporary power for a short while when the electrical service to a home or office goes out.

Most UPS devices are designed for electronics with small noninductive motors, including computers, stereos, and TVs. Devices with large inductive motors require specialized UPS devices.

If you’re not sure if a device should be connected to a UPS, check with the UPS manufacturer.

UPS Size

For a UPS to do its job, it must be adequately sized to deliver sufficient power to all the connected devices. Size refers not to the physical mass of the device but rather to its capacity. Before purchasing a UPS, determine the amount of power used by all the devices you plan to connect to it and the amount of time you want the UPS to provide power in the event of a power outage.

Device Wattage

The amount of wattage the UPS system needs to deliver is a critical factor. A watt is a unit of power defined as one joule per second. When talking about electronics, wattage is measured as the voltage (V) multiplied by the current (I) in a circuit (W = V x I). In this case, the circuit comprises the equipment connected to the UPS, such as a computer, monitor, and peripherals.

Almost all electronic devices have the voltage, amperes, and wattage listed on the label. To find the total, add the wattage value listed for each device. If no wattage is listed, multiply the voltage by the amperage. This produces a value that is the maximum wattage the devices are likely to produce.

Use a portable wattmeter, such as the Kill a Watt meter, to directly measure the wattage used by all your devices.

VA Rating

UPS manufacturers usually do not use wattage. Instead, they use a Volt-Ampere rating. The VA rating is a measure of the apparent power in an AC (alternating current) circuit. Since computers and peripherals use AC, the VA rating is the appropriate way to measure the actual power consumed.

There is an equation for converting wattage to VA. As an example, if a computer and the peripherals have a total wattage of 800, then the minimum VA rating you should be looking for in a UPS is 1,280 (800 watts multiplied by 1.6). Round this up to the next standard UPS VA rating available, most likely 1,500 VA.

UPS Runtime

Runtime is how long the UPS unit can power a computer system at the expected wattage level during a power outage. To calculate runtime, you need to know the minimum VA rating, the battery voltage, the amp-hour rating of the batteries, and the UPS’s efficiency.

The needed values are rarely available from the manufacturer. However, these values sometimes appear inside the UPS manual or technical specifications. If you can ascertain the values, online UPS runtime calculators can do the math for you.

If you can’t find all the parameters needed to perform the runtime calculation, visit the UPS manufacturer’s site and look for a runtime/load graph. There are also online UPS selector tools that help you choose a UPS based on your needs.

The hardest value to uncover is UPS efficiency. If you can’t find this value, substitute 0.9 (90 percent) as a slightly conservative estimate.

UPS Runtime Example

As an example, a CyberPower CP1500AVRLCD uses a 12-volt battery rated at 9 amp-hours with 90 percent efficiency. It can provide backup power for 4.5 minutes to a computer system drawing 1,280 VA.

That may not sound like much, but 4.5 minutes is long enough for you to save your data, close files, and perform a shutdown in an emergency. If you want a longer runtime, pick a UPS with better efficiency, a longer-lasting battery, higher voltage batteries, or all of these. Choosing a UPS with a higher VA rating doesn’t increase runtime. Still, most manufacturers include larger batteries in UPS models with larger VA ratings.

UPS Battery Replacement

On average, a UPS battery lasts three to five years before it needs to be replaced. Many UPS devices provide a warning when the battery needs to be replaced, and a few stop working. You may end up changing out the battery a few times during the life of the UPS, so knowing the cost and whether batteries are readily available is a good idea before selecting a UPS.

Before buying, make sure the UPS provides a pass-through mode that lets the UPS continue to operate as a surge protector when the battery fails.

Figure out how much battery backup you need

How to select an uninterruptible power supply (ups) for your computer

  • Tweet
  • Share
  • Email

What to Know

  • To size your needs: Total watts of your equipment x their total amperage and add 15% of that total to get your total requirement.
  • The difference in UPS capacity compared to its load can increase runtime if significant enough.

This article explains how to determine the right uninterruptible power supply size to fit your needs.

How Big Should My Uninterruptible Power Supply Be?

The three significant factors to consider when setting up a UPS are the intended load (i.e., the combined voltage and amperage of all connected electronics), the capacity (i.e., maximum power output), and the runtime (i.e., how long it can supply battery power for). A UPS is most efficient when the capacity closely matches the overall load without falling below the necessary levels. In other words, you’ll want to avoid using a UPS with a lower capacity than the intended load.

” data-caption=”” data-expand=”300″ data-tracking-container=”true” />

Peter Cade / Getty Images

The necessary runtime for your UPS depends on how long you want or need your connected devices to continue to operate during an outage. Larger batteries or external battery packs (if the UPS supports them) will increase runtime. On the other hand, more devices and more power draw decrease runtime.

Figure out all of the electronic devices you’ll be connecting to the UPS.

Determine both the voltage and the amperage for each device. It should be included in the device’s documentation or listed on its nameplate.

Multiply the voltage by the amperage to calculate each device’s volt-amp (VA) rating, then add all VA ratings together to determine the total VA necessary for your UPS.

It is recommended to exceed your VA totals by 10% to 15% (or more) to provide a bit of a protective buffer and account for growth over time.

To account for this buffer/future growth, multiply your VA total by 1.15 for 15%, 1.20 for 20%, and so on.

Compare your VA total (preferably with at least a 15% to 20% adjustment) to the UPS output/VA rating to find one that’s a good fit.

For example, if you plan to hook up a single M1 Mac mini (2020), which uses a maximum of 39 watts and around five amps if it’s used all day, the VA rating would be 195 (39 x 5). The VA total would then become 224.25 (195 x 1.15), accounting for 15% growth.

How Do I Know My UPS Capacity?

The capacity of your UPS is its maximum power output (AKA VA rating). When shopping for a UPS, the VA rating should be listed along with the type (Standby, Line-Interactive, or On-Line), input voltage, etc., on the box or product page. If you already have a UPS and want to check, the capacity should be in the documentation that came with the UPS and displayed somewhere on the UPS casing itself (likely on one side, the back, or the underside).

” data-caption=”” data-expand=”300″ data-tracking-container=”true” />

How Long Will a 300W UPS Last?

The available runtime for a 300 watt UPS largely depends on the make and model itself and how close to capacity the connected load is. Some UPS will last around three minutes with a full load, some up to five minutes, and so on. If the UPS is operating at a less than full load, it will likely provide backup power for a little longer than it would otherwise. Some UPS may also list their total load runtime, though you can calculate it for yourself if necessary.

How Do You Calculate How Long a UPS Will Last?

The commonly-used formula for calculating the runtime of a UPS is pretty straightforward, but you have to know a few additional values first.

” data-caption=”” data-expand=”300″ data-tracking-container=”true” />

Find the capacity of the UPS battery in ampere hours (Ah). This information should be included with the UPS documentation, on the listing page, or on the battery itself.

Find the input voltage of the UPS.

Determine the total load for the UPS in watts by adding up the watts used by all of the connected devices.

Multiply the battery capacity by the input voltage, then divide that number by the total load.

For example, a UPS with a battery capacity of 150Ah, 10V of input voltage, and a load of 700 watts should handle a runtime of around two minutes (150 x 10, divided by 700).

Choosing the best uninterruptible power supply largely depends on how you use it. For instance, if you are picking a UPS for your Mac or PC, you should consider the device wattage, VA rating, and runtime, along with the size.

An uninterruptible power supply, or battery backup, can help protect your computer. It can provide backup power when the electricity goes out, act as a power “conditioners” to keep electricity flowing to your computer and accessories free from drops or surges, and decrease noisy power sources.

Introduction Features
Principles Classifications
Engineering Data Further Information
Explanation of Terms Troubleshooting
  • Uninterruptible Power Supply(UPS)
    • Products
  • What Is a Uninterruptible Power Supply (UPS)?
  • Function
  • Classifications
  • Mechanism
  • Selection Method

What Is a Uninterruptible Power Supply (UPS)?

A UPS, or a uninterruptible power supply, is a device used to backup a power supply to prevent devices and systems from power supply problems, such as a power failure or lightning strikes. A UPS can help prevent power supply problems that can often occur on a production site, such as an instantaneous voltage drop and a power failure.

How to select an uninterruptible power supply (ups) for your computer

If power supply to devices stops because of an instantaneous voltage drop or a power failure, devices such as PCs or registers shut down abnormally, which can damage hard disks and corrupt the data. A UPS can supply power to devices from a built-in battery for a given period of time during an instantaneous voltage drop or a power failure to protect devices and important data.

There are two major classifications of UPSs: DC input/DC output models and AC input/AC output models. Select the optimum UPS for your needs based on the type of power supply, load capacity, and other specifications of the equipment and devices that you want to backup. You can also use a UPS together with a switch mode power supply to further increase your options.

How to select an uninterruptible power supply (ups) for your computer

A DC-DC UPS is the optimum option for backing up devices with a DC input power supply.

How to select an uninterruptible power supply (ups) for your computer

An AC-AC UPS is the optimum option for backing up devices with an AC input power supply.

During normal operation, the input power supply bypasses the UPS and is output as-is. During backup operation when a power failure or an instantaneous voltage drop has occurred, the UPS changes to inverter operation with power supplied from its internal battery.

How to select an uninterruptible power supply (ups) for your computer

Check the power consumption (W) of the device that will be backed up by the UPS, and select a UPS that has an output capacity greater than that amount.


ENERGY STAR makes it easy to find the UPS Battery Backup to fit your needs. Using our ENERGY STAR product finder, you can select from hundreds of certified efficient models from the best, most popular and most trusted brands you rely on to keep your equipment safe — like APC, Eaton, Liebert, Tripp Lite, and others. In addition, you can filter the list of models by specific attributes such as:

  • Application (e.g., consumer, commercial, data center)
  • Active output power
  • Product type
  • Rated output voltage

An Uninterruptible Power Supply (aka a UPS Battery Backup) protects vital connected equipment — computers, servers, and telecommunications equipment — from power outages. During an outage, that small UPS Battery Backup under your desk at work gives you enough time to save your spreadsheet and properly shut down your computer. For data centers, a massive, 8-ton UPS Battery Backup affords operators a chance to bring on backup generators during a power outage. See our buying guidance for information on how to select the right model for your situation.

Regardless of whether you need one under your desk or in your data center, look for UPS Battery Backups that have earned the ENERGY STAR label to save energy and help protect the climate. They are third-party certified to be energy efficient and reduce energy waste by up to 52 percent compared to conventional UPS Battery Backups by minimizing losses in inverters and transformers, offering modular units to avoid oversizing, and/or providing an “eco-mode” of operation.

Interested in energy efficient servers, data center storage, or networking equipment? Learn more about ENERGY STAR certified data center equipment.

Interested in easy ways to be more energy efficient in your data center? Review ENERGY STAR’s 5 Simple Ways to Avoid Energy Waste in Your Data Center.

  • How to select an uninterruptible power supply (ups) for your computer

What happens when the power goes out at your home or office? Laptop and mobile devices can switch over to their built-in batteries. However, anything without a battery immediately shuts down. An Uninterruptible Power Supply, or UPS, offers battery power to any device connected to it.

Types of UPS Devices

Only three types of UPS devices exist: standby, line-interactive, and online. Standby units cost less and are the most common. If the model doesn’t mention a type, then you’re looking at a standby unit.

Standby UPS

A standby unit charges its battery and waits for a power outage. Once the power goes out, the UPS switches over to battery power. A 20-100 millisecond delay occurs between the switch. This delay falls well within most device tolerances to prevent power failure.

Line-Interactive UPS

Line-interactive UPS devices work very similarly to standby units. However, these units include a transformer that offers your devices more protection from brownouts and power sags. In general, we recommend spending the extra money on one of these. Your devices will thank you.

Online UPS

These units provide power to devices exclusively through the batteries. The batteries charge constantly unless the power goes out. This type of unit offers the most protection, but that protection costs much more. Typically, prices run 200-400% higher than a line-interactive UPS. Unless you run a data center, you don’t really need to pick this option.

How Much UPS Do You Need?

Calculate Wattage and VA

First, you need to know how much power your devices use. You can measure this in a couple of ways. The accurate method involves using a power meter (like the Kill A Watt Meter) to measure the exact wattage for every single device. The meter will supply you with real-usage numbers.

The conservative method involves looking at the power ratings on each device you’ll have connected (computer, monitor, etc.). For example, your computer might have a 400W power supply, and your monitor might use 100W. In reality, devices actually use less power than their rating, so this is a safe estimate.

No matter how you get the numbers, add the wattage for each device together. From our example, our devices use a total of 500W. Multiply that total by 1.6 for your minimum Volt-Amperes (VA). Volt-Amperes are used to measure the capacity of UPS units. We’ll use this number to select the right UPS unit next.

Select Runtime

Unfortunately, there’s no good way to calculate runtime. Instead, UPS manufacturers like APC, CyberPower, and Tripp Lite offer tools to help find the right UPS unit for you. Armed with your Watts and VA, take a look at one of these sites:

Add your VA and/or Wattage to filter the list down to UPS units that will provide the right amount of power. Each unit varies when it comes to runtime.

Choose the runtime that matches what you want to accomplish. In general, the goal isn’t necessarily to keep working. At a minimum, you just need enough time to save your work and shut down your system. Regardless, you should be able to pick out the UPS unit that best fits your needs!

Looking for More Tips?

Blog posts with various IT tips and news are released every Friday. We publish new episodes of Tech Tip Tuesday as often as we can. You can view previous episodes in our Tech Tip Tuesday library. Click the Sign Up or Subscribe button on this page to subscribe and receive every tip directly in your inbox each week. Pit Crew IT Services can also help your organization with any IT needs you might have. Get started with a free consultation using the button below.

The main role of UPS is to protect your computer from voltage fluctuations and power outage. Power outage depends on your geographic location and area of residence; while voltage may increase or decrease depends on the workload your computer needs.

Voltage fluctuations lead to a sudden break for your computer and related devices forcing them to restart without prior alert. Those sudden breaks and restarts result in a loss of unsaved documents and a damage in the computer on the long run, so UPS is a worthy investment because it protects you from buying a brand new computer. You may choose to have UPS because you live in an area where voltage fluctuations and power outage are frequent, or to avoid losing important files while working on them, or both.

Next paragraphs we explain the technologies used in UPS devices. You can compare prices of UPS devices from here.

UPS devices technologies

There are three basic technologies that determine the right UPS device, On-line, Off-line and line-interactive.

On-line technology

In On-line UPS devices, the electrical current that operates devices comes exclusively from the built-in battery, but it gets converted from direct current DC to Alternate Current AC to protect devices. While In normal operating conditions battery is constantly charged with power while it provides current to the plugged device. In the case of a power outage, the battery continues to feed the devices with power for a period of time varies from one UPS device to another.

This type is the safest and highest quality; however, its price is expensive compared to other UPS types; and the noise of the cooling fans make them unsuitable for home use. This type is used mainly in vital places (company servers’ room, for example).

UPS On-line device with 1000 VA capacity and 10 kg weight

Off-line technology

Off-line UPS feeds the computer associated with it directly from the power source of the building as long as the level of voltage is appropriate; when the building current gets lower than required UPS provides power to the devices from the built-in battery. This switch from the building power to the battery power causes a slight cut in the current that flows to the computer plugged in, but this cut lasts for fractions of a second so it does not affect the computer because modern computers are equipped with amplifiers to face such short cuts in power; but it may affect devices that are more sensitive than computers.

Off-line UPS devices feature small sizes and cheap prices, suitable for desktops.

Off-line UPS device with 600 VA capacity and 2.7 kg weight

Line-interactive technology

Line-interactive UPS Devices (sometimes called in-line) work in a similar way to the off-line ones with one difference, Line-interactive UPS is able to compensate the lack of power voltage instead of using the battery. This type is ideal for countries or places where the power supply quality is low.

SMEs prefer this type of UPS devices to protect their computers, network attached storage servers NAS and routers.

Line-interactive UPS device with 800 VA capacity and 4.9 kg weight

If you are going to buy a UPS device to protect your desktop computer then it is better to choose the Line-interactive type; for a company or an organization it is advised to choose the On-line type.

Choosing your UPS device

UPS technology type is not the only criterion; what is more important is the ability 0f UPS to operate devices associated with. This ability is measured by VA (kVA = 1000VA).

To identify the required UPS capacity you must specify the devices you want to link (computer, monitor, printer, etc …), then you will have to determine the total power consumption of each device by Watt, after that you will multiply the total power consumption by 1.5 to get the required UPS device capacity. For example, If the total consumption is 500 watts, then UPS capacity must be 500*1.5=750VA at least.

Another example, a computer with a i3processor, 8GB memory, GeForce GTX580 card, Blu ray discs reader and 24 inch LCD screen. In this case, the total power consumption is up to 500 Watt so UPS capacity must be 500*1.5=750VA at least. Same rule applies for all devices you want to protect (20 watts consumption modem, 10 to 100 watts consumption Speaker, 10 watts consumption inkjet printer).

Sometimes UPS capacity is identified by Watt; in this case you do not need to convert to VA.

You should also pay attention to ports number in UPS and the compatibility of devices you want to connect.

How to select an uninterruptible power supply (ups) for your computer

Most folks associate an uninterruptible power supply (UPS) with storms and power outages. While backup power can keep your computer setup protected from summer storms, an uninterruptible power supply can also keep your costly equipment protected against brownouts, voltage spikes, electromagnetic, and radio frequency interference. But which UPS is right for your needs? Are you a gamer? Are you editing video footage? Maybe you’re an IT or data professional running servers, or a small business owner looking to protect your POS, computers, and more. Even the casual power user can safeguard their system with a UPS. Check out the below recommendations for find the UPS that’s right for your needs.


Whether streaming gameplay or playing competitively, the last thing you need is your game grinding to a halt. Gaming UPS systems like the APC Back-UPS Pro Gaming usually feature solid output with enough wattage to support your rig and peripherals. A good gaming UPS provides built-in surge protection and may also feature some outlets without battery backup power. These outlets can be used to accommodate non-essential peripherals that might occupy your gaming space, but that would not need to remain powered during an outage. If possible, gamers should also opt for a UPS with an LCD screen. If an outage causes you to switch to battery power during gameplay, this display allows you to monitor power-related specifics at a glance, without breaking your concentration.

Video Editors

Video editors face a unique set of challenges when it comes to backup power. Uninterruptible power supplies like the APC Smart-UPS X 1500VA Rack/Tower LCD 120V offer video editors plenty of power for heavy loads or overprovisioning. In addition to constant and smooth power input, these users also benefit from clean power. For this reason, the best UPS systems for video editors feature a pure sinewave output, ensuring the smoothest possible transition from mains power to battery backup juice. Automatic voltage regulation (AVR) is also critical in this regard, correcting voltage irregularities without switching to battery power and ensuring constant, clean power. Lastly, a preinstalled network card allows for easy remote management.

IT and Data Professionals

Rack-mountable uninterruptible power supplies provide convenient integration into an existing server environment. The best UPS systems for these environments, like the APC Smart-UPS X 3000VA Rack/Tower LCD 100-127V, provide ample outlets that allow for the connection of multiple NAS arrays, while expansion slots accommodate networking cards for optimized connectivity. Hot-swappable batteries ensure clean uninterrupted power while a battery is being replaced. Furthermore, UPS systems optimized for data environments usually incorporate specific connectors for external battery packs, allowing for extended run time during an outage. Another thing to check for when selecting a UPS for this use-case is controllable outlets. These outlets can be remotely turned on or off via a network connection, allowing you to cycle power, shed loads, and prevent unauthorized use.

Small Business Owners

Small business owners may need to protect a range of equipment, including computers, POS systems, networking equipment, and surveillance systems. Ideal UPS systems like the APC Smart-UPS C Battery Backup & Surge Protector with SmartConnect enable easy remote management via a network connection, including unattended shutdown in the event of an emergency. Special attention should also be paid to run time and load, while plenty of battery-backup outlets are a must to ensure critical systems like registers and cameras remain functioning. User-replaceable and hot-swappable batteries are another boon, allowing you to stay operating longer during an outage. Special consideration should also be given to serviceability and manageability features, such as battery notification, alarm systems, and online efficiency, which can lower cost of ownership and boost your bottom line in the long run.

Power Users

What if you aren’t a gamer, video editor, or someone who needs beefed-up backup power? Even causal or power users can improve equipment protection by investing in an economical UPS like the APC BE600M1 Back-UPS with Battery Backup. Power users will benefit from several outlets with a mix between battery backup and surge-only protection. Plus, convenient USB charging can keep a cellphone or tablet juiced up while you’re working. Battery failure and wiring fault indicators will alert you of hiccups before they affect your equipment, and automatic self-testing ensures batteries can be replaced before they fail. Finally, power users who want to stay productive through an outage should also consider UPS systems with hot swappable batteries, allowing them to extend run time by switching batteries without losing power.

Do you currently use a UPS? If not, which of these systems is right for you? Leave any questions or thoughts in the Comments section, below.

How to select an uninterruptible power supply (ups) for your computer

UPS is an acronym for “Uninterruptible Power Supply“. It is composed of three parts: control circuit, battery pack, and inverter. UPS can charge its battery pack through power grid (mains), so when power grid has power problem, UPS can release power loads to connected equipment for use.

It’s commonly though UPS can only provide load power when there is a power outage. In fact, that is not the only function in UPS. In addition to transiently providing load power, UPS also features voltage stabilization, filtering, surge and noise prevention, etc. It can provide pure power for high-end audiovisual equipment while ensuring the normal operation of computer reading and writing data. This will reduce equipment failures and data loss at the consumer’s end.

With the popularization of UPS, it has been fully used in all walks of life and under various environments. The characteristics of UPS in different application fields are introduced below:

Home Use:

Most people lack the concept of protecting information and communication Technology Equipment (ICT) through UPS and often neglect power problems (power outages, instantaneous power interruptions, abnormal over/under-voltage, instantaneous frequency changes, etc.). This is a potential crisis for ICT equipment. In mild conditions, equipment anomaly or crash may occur; in serious conditions, permanent equipment damage may result. Equipment purchase costs are less of a problem; Failing to save the stored files in the equipment is frustrating. The concept of UPS use is like purchasing insurance. With this insurance, there is no longer a need to worry about causing harm to ICT equipment due to power problems.

Generally speaking, the first factor to consider when purchasing a UPS is power capacity. The first thing to do is to evaluate which equipment are going to connect with UPS. For instance, if a personal computer has a built-in 750W power supply, a 27-inch screen has a built-in 150W adaptor, a multi-tasking printer has a 90W adaptor, a wireless router has a 20W adaptor, and a NAS Ethan has a 90W adaptor, the total load of this configuration is about 1100W. Then, the choice of UPS will be based on the budget. An offline UPS power factor is about 0.6. With this configuration, a product with a rating of at least 1,100W/0.6=1833VA should be purchased; the line interactive power factor is about 0.7, a product that is larger than 1,100W/0.7=1571VA should be purchased; an online power factor is about 0.9, a product that is larger than 1,100W/0.9=1,222VA should be purchased. We usually purchase a UPS with higher capacity in exchange for longer power supply time. Selecting a UPS with more than double the required load capacity will not only achieve longer run time during power outage, but will also serve as an expansion capacity when supplementing ICT equipment in the future.

A full range of FSP models for home applications including Nano, NanoFit series. If you have high-end audiovisual equipment at home, it is recommended to use line interactive UPS such as Eco, FP, and iFP series, etc. the voltage stabilization can keep the quality of your user experience. Connecting UPS with personal computers, small routers, NAS, small regional network equipment, workstations will ensure cloud data access without interruption. Connecting the security and monitoring systems to UPS will also aid in maintaining the home environment without security breaches due to power interruptions.

Server Computer Room and Data Center:

The computer room is the most important place for processing digital data and storage systems. The network equipment, information equipment, air-conditioning equipment, monitoring equipment, power generation system, and UPS system in the computer room all require a stable power supply, so as to maintain 24-hour normal operations without interruptions. It is especially so during UPS planning that has no room for negligence.

The power requirements of computer rooms vary greatly depending on their size, ranging from several thousand to tens of thousands of watts. For example, a small computer room equipped with three network cabinets that consume 3,000W, one network wiring cabinet that consumes 1,000W, and ten server cabinets that consume 50,000W. All these requirements need 54,000W power in total. If an online UPS with a power factor of 0.9 is selected, a product with 54,000/0.9=60,000VA is needed. In order to entertain the possibility of computer room expansion, it is recommended that a modular model that can be expanded in parallel be selected to achieve N+X backup results.

FSP Group has launched UPS for computer room environments, including Custos 9X+, Eufo, EPOS, Mplus series, etc. The Mplus modular model features hot-swap repair without affecting continuous power supply by other UPS. The equipment size can be planned and expanded at any time to suit actual needs, thereby fully using the computer room space. It also has the advantage of achieving high conversion efficiency to save wasted power and remote monitoring of the UPS’s operational status. As for the online UPS, in addition to providing you with stable and uninterruptible pure power, 50/60 Hz output power is accurately provided targeting precision equipment. Additionally, power can be supplied based on the priority of important equipment. It is your best choice for planning computer rooms and data centers.

Medical Institutions:

Compared to business and industrial fields, medical institutions have more stringent requirement standards for UPS. Regardless of the size of a medical institution, stable and pure currents are needed at all times to ensure the accuracy of all diagnostic results and safeguard the safety and lives of patients. Patients’ clinic consultation data and medical records are important diagnostic data for medical institutions. Related routers, servers, storage equipment, etc. must come with high-standard UPS.

When various power supply problems occur, depending on the importance, hospitals have sockets in three colors. Other than regular white sockets, red sockets will have power interruptions for seconds during a power outage and wait for power to be supplied by a generator. Black sockets are of the greatest importance. They have to be connected to the UPS at all times, such as those in operating rooms, emergency rooms, intensive care units, patient life support equipment, etc. According to the differed sizes of medical institutions, UPS lower than 120KVA is suitable for hospital data centers, 120

400KVA is suitable for building-related firefighting and surveillance equipment. Single-phase UPS can provide longer backup time and is thus suitable for use on medical devices.

In order to maintain the smooth operation of all the areas of a hospital, without interruptions, the online UPS can provide a power source of the highest quality. Additionally, targeting instruments that vary in importance, different power requirement arrangements are made. The hot-swap function can enable UPS to support each other in supplying power. The high conversion efficiency can bring out the highest efficiency of every kilowatt, making the hospital the most reassuring treatment site for patients.

UPS applications are ubiquitous. In the succeeding part, how other application fields choose UPS will be introduced.

Lots of features for a small cost

Protection in any location

Losing power is never fun, but it can also seriously mess with your electronics. Computers, external hard drives, home Wi-Fi networks, and more all feel the negative effects of an outage. So, it’s important to create a plan of action now, to keep your home or your business, or both, running during these possible future blackouts. One important part of your plan should be to consider the best battery backups (uninterruptible power supply, or UPS), which will automatically take over when the power drops or goes out entirely.

But there’s no one solution that’s perfect for everyone. Some might need a more powerful and versatile solution—particularly if you’re looking to back up the equipment in your business. Or maybe you have computers and laptops that are particularly sensitive. And you’ll find that UPS models have a broad price range—you can buy one for under $100 or spend thousands of dollars.

To help you narrow those choices, we’ve put together a list of the best 5 UPS models currently available.

Even if you’re not prone to power outages, many UPS models also include surge protection features. An automatic voltage regulator smoothes over brown outs and spikes without needing to change your battery. It’s one of a number of capabilities you’ll want to look for in a UPS.

How we selected the best battery backups

For the majority of the UPS models in this guide, we focused on the home user, which is why we selected units that were less than $300. However, for one, Best UPS for business, we selected a more expensive model, since most small business owners are likely to pay more for a more robust UPS that can handle more machines.

Next, we prioritized UPS options that output as a clean sine wave form, instead of a simulated sine wave form: This feature is important for more sensitive computers, like gaming systems, and audio equipment.
We also considered a number of other features that we considered important—for instance, we looked for UPS models that included surge protection features, like line interactive topology, which uses an automatic voltage regulator to normalize any dips or spikes in power in active (or non-battery backup) mode. We also considered other features: How many outputs did the UPS have? How many outlets were both battery-and-surge-protected outlets? How many outlets had only surge protection? Plus, we considered USB ports, the length of the power cord. These details can sound pedantic, but they can make a huge difference in day-to-day use.

What to consider when buying the best battery backups

If you’re looking to buy a UPS, you’ll find that there’s a rather large range in prices—from less than $100 to more than one thousand dollars. So, how do you choose? Use the following guide to help you make your decision. Here are some factors to consider before making your purchase:


When you’re looking to buy an uninterruptible power supply, or UPS, which is a device that will not only provide power to various devices, like a laptop or wireless router, but it also serves as a surge protector. Depending on how powerful your UPS is, you can have it provide battery backup power to many different devices. However, you’ll need to make sure that your supply has enough output power for the job. In general, the best battery backups can output at least 400W.

Sine wave inverter

UPS models include a number of different features, but you’ll want to focus on a couple, depending on what you want to back up. A sine-wave inverter allows a UPS to produce a clean sine wave form, which is the best type for power output. In contrast, some inexpensive models output a simulated sine wave form, which can be problematic for some higher-end gaming laptops and audio gear. Another key feature is to look for line interactive topology, which in some UPS models, use an automatic voltage regulator to compensate for small dips and spikes in the active power coming into your house. So, this feature acts as a surge protection for your computers and system.

Endurance and outlets

A unit’s longevity depends on how powerful your UPS is, as well as how it’s configured. For budget or low-end UPS models, you’ll only be able to power devices that aren’t as powerful. Also, lower-end UPS models won’t let you run your computers and other gear as long. (This is called “run-time” and some manufacturers include this information on the product sections of their websites.) Be sure to research how much power you’ll need to run your devices in case of a backout.

Most UPS models include a number of outlets that include both battery backup and surge protection and outlets that only have surge protection. Be sure you factor that in when making your battery backup plan.

Device compatibility

There are some types of products that you won’t be able to run—such as a refrigerator or microwave, which would be too taxing on the UPS. Also, there are some smaller products that just draw too much power. Hair dryers fit that description.

It’s also important to remember that a UPS isn’t meant to take the place of a home-generator, which has more robust power capacity. But for many consumer electronic devices, even monitors and power PCs, a UPS should give you the ability to run them, at least for a short amount of time. (Again, be sure to study the features and specs of the USP models you’d like to purchase to see if it will back up your system effectively.)

A UPS can prevent disaster striking when the power is cut, by seamlessly switching to battery power to continue to power your devices until either the main power is restored, or you’re able to safely shut down your device. So buying a UPS is the first thing that one should install with their computer system, especially if they haven’t any overall power backup at their home. In case of power cuts you would need to select a UPS which has the ability to give sufficient backup time while satisfying other requirements.


You have successfully cast your vote

Login to view result

Here are some of our top choices of UPC for computers:

APC Back-UPS System

The APC Back-UPS is an ideal power backup and protection for home offices, desktop PCs, home entertainment systems, Wi-Fi-routers, and electronic devices. It defends your digital experience from any power disruption and ensures quality and uninterrupted power supply to your electronic devices. This UPS provides three Indian 2/3 pin power sockets, which are battery back-up and surge-protected outlets. It protects your hardware and data during power outages, surges, and spikes.

APC Back-UPS has AVR Technology which provides protection from wide voltage fluctuation and also compatible with a generator that is ideal for Indian power condition. Other add-ons of the inverter include, battery failure notification, Intelligent battery management, and a periodic battery self-test to ensure early detection of a battery that needs to be replaced.

Zebronics 600 va UPS-U725 for Desktop

How to select an uninterruptible power supply (ups) for your computer

This efficient UPS from Zebronics is a line interactive UPS that comes with overload protection that helps in saving your connected device from damage cost by overloading. The UPS supports sleep mode charging and it also comes with an LED indicator and audible alarm that alerts the user in case of a fault. Additionally, it regulates the output voltage according to the given input voltage in order to provide us a constant output waveform.

For devices that consume a high amount of power, this UPS offers a battery backup of around 28 minutes and for low power consuming devices, it can offer a backup for 3 hours continuously. Thus, you can always rely on this backup system.

Artis PS-600VA 600VA Line Interactive UPS

How to select an uninterruptible power supply (ups) for your computer

The Artis-600VA Line Interactive UPS offers a wide input range of 140-230 VAC, Cold Start function, and Generator Compatible features that never let you suffer. The cold start feature reserves some battery even when the UPS is out. The microcontroller of the device ensures impressive performance and reliability for maximum performance. It is equipped with a heavy-duty battery, and the processor gives Simulated Sine Wave Output, which provides better performance than square wave and prevents computer units from shocks.

The advanced battery warning feature alerts you when the battery requires charging. It also provides information and alerts you when there is a battery failure.

Microtek Tuff Power Pro+ 650VA UPS

How to select an uninterruptible power supply (ups) for your computer

Microtek is a reputed name in the section for home inverters. The Microtek Tuff Power Pro+ 650VA UPS is an ideal choice to provide complete protection to your PC. This UPS is a simple one but is capable of protecting your PC from power fluctuations. It is very helpful and is compatible with most of the devices.

Talking about the reliability of the device, it is one of the most reliable units and is capable of handling the voltage fluctuations between 140-300 volts. An additional helpful feature of the Microtek Tuff Power Pro UPS is the extended battery life.

Emerson Liebert iTON CX 600 VA Line Interactive UPS

How to select an uninterruptible power supply (ups) for your computer

The Emerson Liebert iTON is a Line Interactive UPS, which means it regulates the power coming through it and makes the change in the voltage itself to suit the connected devices. It’s a necessary feature to have, which prevents voltage fluctuations. It works on a simulated sine wave, which is not as good as a pure sine wave but does its job quite well, especially if you don’t have too much load.

The presence of the autotransformer in the UPS system protects your expensive equipment from damage in case of severe voltage fluctuations. The battery provides sufficient runtime for you to shut down your computer. The battery has a recharge time of six hours.

DISCLAIMER: The Times of India’s journalists were not involved in the production of this article.

What questions should you answer when selecting a UPS to get the right one?

How to select an uninterruptible power supply (ups) for your computerOne of the most popular requests we get here at Minuteman is how to select the right UPS to back up a given system of equipment. There are several questions that need to be asked when sizing any level of equipment to ensure the proper unit is selected.

Luckily the process can be broken down into 5 simple steps – read on for our guide to help you correctly identify what to look for when choosing a UPS unit for your equipment.

1) The first and most crucial question is: What piece(s) of equipment is being backed up and what is the electrical draw?

We often get requests from customers looking to back up computers, servers; DVRs etc. There are no set rules for how much electrical draw any piece of equipment will have. Depending on how they are set up and what peripheral gear is attached, the electrical draw is a case by case scenario.

The majority of the time, the equipment you are trying to back up will have this listed in either watts, amps, or Volt Amps (VA) on a label located on the back of the device. If not there, a quick Google search for your equipment can return the electrical load in most cases.

How to select an uninterruptible power supply (ups) for your computer

Electric outlet on the textured wallpapers. US style.

2) What are your input and output voltage requirements?

This is the voltage that the building that you will be plugging your UPS into will have. There are several different levels of voltage your equipment can utilize, including 120, 208, 220, 230 and 240, with 120 and 208 being the most common. Most equipment in a residential property will use 120 volts, while a commercial building will often have 208 for larger equipment. If the building requires something higher at 220, 230 or 240 that can change the configuration of the UPS greatly.

How to select an uninterruptible power supply (ups) for your computer3) What runtime are you looking to get from your UPS?

To correctly size a UPS, deciding how long the attached equipment will be needed in the event of an outage is a crucial step. Example: If you are looking to back up a single item with a 400 watt draw for 10-15 minutes the UPS configuration will be completely different verses that same 400 watts at 4 hours. Think of it in terms of a give and take or “If this___ than that___.”

4) How critical is the application being backed up?

There are multiple levels of UPS topography. Here is a quick tutorial on the differences:

How to select an uninterruptible power supply (ups) for your computerStandby: This is the most basic level of UPS. If there is any problem with the electricity (surge, sag, spike, blackout or brown out) the UPS will automatically switch to battery power. This has a 6-10 millisecond switch over time.

How to select an uninterruptible power supply (ups) for your computerLine Interactive: This is a secondary level that is better suited for protecting higher end equipment. This level of UPS has Automatic Voltage Regulation (commonly referred to in the Industry as AVR). This UPS is designed to regulate surges, spikes, and sags in utility power to keep it at is correct voltage all before going to battery. Additionally, this saves on battery life. There is a 6-10 millisecond switch over time.

How to select an uninterruptible power supply (ups) for your computerOnline: This is the top level of UPS on the market today, should the equipment you are looking to protect be “Mission Critical.” This UPS is designed to condition the power coming into equipment and includes 3-phase UPS systems. Utility electricity often comes into a facility in a distorted state due to electrical noise. Online UPSs are constantly filtering out these problems, and will provide pure sine wave, undistorted electricity as it flows into your equipment. There is no switch over time.

Whatever the application is, the solution should fit into one of these different UPS topographies.

5) Finally, what physical parameters are we dealing with when trying to find a solution that fits?

Do you want the unit to be tower or rackmount? If rackmount, how much space do we have? These are questions to ask when deciding on the physical footprint your UPS will leave.

To choose the right UPS, be sure to figure out business needs, power supply size requirements and how long your backup systems must last during downtime.

How to select an uninterruptible power supply (ups) for your computer

Uninterruptible power supply selection starts with a plan and a business purpose. The hardware’s goal is to maintain power when the utility service quits, but admins should determine for how long, how much redundancy is necessary, how big the supply must be, if it must eliminate power anomalies and how often the system must be online to provide backup power.

There are several uninterruptible power supply (UPS) options, but one size does not fit all. IT teams should figure out what they need and shouldn’t overlook full bypass control requirements.

Reliable generators don’t require long ride-through times, so admins may consider a flywheel UPS. It takes less space than other battery backup systems, has no expensive battery replacement and can cost less initially. Backup duration may be only 15 to 30 seconds, depending on the system’s load size and configuration, but this is ample time for any good generator. Plus, a flywheel UPS doesn’t require cooling.

Admins with exceptionally large data centers might consider a Diesel Rotary UPS, which combines the generator and UPS into one system. They’re economical for larger facilities and can also save space and money but can have specific mechanical maintenance considerations.

For most organizations, a battery-based UPS is likely the ideal choice. Most options now have power factors of 0.95-1.0, meaning a 100 kVA UPS can actually deliver 95-100 kW of real power to any load.

Battery UPSes are now transformerless, which makes them more efficient than previous generations. It’s common to see full, double-conversion UPSes with efficiencies above 97%, and efficiencies can remain at 96% or more with a rated load of 30% to 40%.

This efficiency is an advantage for 2N redundant systems, where each UPS must run at less than half load to maintain the redundancy. High-efficiency UPSes also minimize the effectiveness of any Eco Mode, which runs the UPS in Bypass Mode until an interruption occurs.

Eco Mode runs IT systems on utility power most of the time and only switches to full double conversion when necessary. Admins who minimize conversion losses over time may gain a percent in efficiency, but the risks of switching delays or failures means IT teams should seldom use it, especially with unstable power.

After admins decide on a UPS type, they must examine the available battery technologies. The market now has three main choices, and the options are all different.

Very large UPSes still use flooded lead acid batteries, or wet cells, which last at least 25 years. They’re large, heavy and require professional maintenance, special rooms with hydrogen detection, exhaust fans, acid spill containment, showers and eyewash stations.

The main alternative has been valve-regulated lead-acid (VRLA) batteries, also known as sealed cells. Admins can place these almost anywhere without special precautions, but they require replacement every three to five years, especially if unstable power causes multiple discharge and recharge cycles. Long-life versions are more expensive and may last 10 years but might still require several costly replacements over the life of the UPS.

New Lithium-ion (Li-ion) batteries have longer lifespans than VRLA batteries. The industry is still learning about these batteries and discovering new chemical configurations. But unlike VRLA’s, usage does not affect lifespan as much. Admins can partially discharge and recharge Li-ion cells many times without reducing lifespan, plus they’re smaller and lighter weight. Most people still associate these batteries with consumer devices such as cellphones or tablets.

But UPS Li-Ion battery chemistry or packaging is not anything like the ones that phones or smaller devices use. They’re safe and admins can install these batteries in most places. They have a higher initial cost than VRLA batteries and are not compatible with every UPS, but they do pay for themselves over the long term. There are even UPSes with Li-Ion batteries that work at the higher temperatures in line with ASHRAE TC 9.9 recommendations, which can save energy.

The biggest cost mistake is oversizing — both for UPS capacity and battery duration. Admins can use modularity to address this issue. IT teams no longer must buy a UPS sized for future growth.

Instead, organizations can buy system frame capacity for future growth but don’t need to completely populate it; if the overall load grows, admins simply just add more capacity.

If an organization doesn’t use the full system, then it hasn’t spent unnecessary money. And if the load reduces, admins can remove modules and keep them as spares, so the UPS always runs at its optimum efficiency.

Moreover, admins can add redundancy at minimal cost with a modular setup. If organizations have a 100 kW UPS with five 20 kW modules, admins can add another module for N+1 redundancy without the need to buy another 100 kW UPS.

IT teams can also use modular batteries to extend available backup power, but the amount of battery power they should use can vary. With redundant generators, five to 10 minutes of backup power is plenty. A single generator may require more in cases of startup issues, but most UPSes run only 30 to 45 minutes without cooling; this means an hour of a UPS power is more than enough for orderly shutdowns.

For smaller data centers, admins can consider a distributed UPS. With the placement of modular UPS cabinets in each rack, organizations can save space and branch wiring cost. Admins can even install one modular unit, plus small, distributed rack-mounted units for truly critical systems. These small UPSes are just as reliable and efficient today as their bigger counterparts.

Different Technologies Designed to Meet A Variety of Different Needs

All three basic uninterruptible power supply (UPS) technologies have their place in protecting today’s distributed IT infrastructure especially on the network edge. Each technology has its advantages and each may be necessary for configuring cost effective power protection, especially in complex systems. Selecting a UPS for your particular application requires an examination of a number of factors. The load size, location and criticality of the equipment to be protected are key, as well budgetary considerations, when choosing a UPS for power backup.

The three major types of UPS system configurations are online double conversion, line-interactive and offline (also called standby and battery backup). These UPS systems are defined by how power moves through the unit.

Online Double Conversion

AC power is stable and clean upon generation. But during transmission and distribution, it is subject to voltage sags, spikes and complete failure that may interrupt computer operations, cause data loss and damage equipment. When it comes to safeguarding critical IT loads, only online double conversion technology protects fully against all these power problems, providing the highest levels of security for networks.

An online UPS system is usually called double conversion as well because incoming power is converted to direct current (DC) and then converted back to AC. This AC-DC/DC- AC design ensures an increased degree of isolation of the load from the irregularities on the main supply.

The online UPS takes the incoming AC power supply and converts it to DC using a a rectifier to feed the battery and the connected load via the inverter so that no power transfer switches are necessary . If the main AC input fails, the rectifier drops out of the circuit and the batteries keep the power flowing to the device connected to the UPS. When AC input power is restored, the rectifier resumes carrying most of the load and begins charging the batteries.

Because power runs through an online UPS continually, output is a perfect sine wave. This type of UPS protects the critical load from virtually all power disturbances, including subtle harmonics and waveform distortion.

This means the quality of power from online UPS is significantly better than that of other technologies. Offline and line-interactive technologies reduce the impact of spikes, surges and sags by either clipping the peaks and valleys, boosting power or switching to battery backup. Within the normal track of an electrical sine wave, however, most power fluctuations are left alone. Online UPS regenerates the sine wave, not just conditioning of the raw utility supply.

An online UPS d elivers continuous, high-quality AC power to equipment with no break when transferring to battery, protecting equipment from virtually all power disturbances due to blackouts, brownouts, sags, surges or noise interference. A true online, double-conversion UPS provides 100% power conditioning, zero transfer time to battery, no change in output voltage and better transient suppression than line-interactive units.

Online double conversion is the most common UPS mode of operation used for protecting large data centers by providing the highest level of power quality to the load always. Online systems also provide frequency regulation, essential for use with backup generator systems to protect from variations common at generator start up.


Line-interactive UPS systems provide both power conditioning and battery backup. This technology is particularly effective in areas where outages are rare, but power fluctuations are common. Line-interactive UPS systems support a wide range of input voltage fluctuations before switching to battery backup.

Beyond battery backup, line-interactive UPS provides far better control over power fluctuations then offline systems. The critical advantage of line-interactive UPS is the voltage boost circuitry and the range of input voltage that that UPS accepts. The wider the range, the more total protection you will have.

Line-interactive UPS technology provides power conditioning with a 4-6 millisecond break in power when transferring to battery back-up and protects against the most common power problems experienced in a network. Here the UPS also monitors the voltage level and balances under and over voltages. This technology provides a good choice between reasonable protection and moderate operating costs.

With line-interactive UPS, the inverter becomes part of the output and is always on. The inverter can operate in reverse to charge the battery while AC input is normal, and switch to battery power when input fails, which provides filtering and voltage regulation. Line interactive UPS systems rely on the battery to condition power so this type tends to drain its battery more frequently than online UPS systems that condition power through the double-conversion process.

When AC input power fails, the unit’s transfer switch opens and the power flows from the battery to the UPS output. With the inverter always on and connected to the output, line-interactive UPS provides additional filtering and yields reduced switching transients when compared to a standby UPS. Line-interactive UPS systems are typically used in rackmount applications below 5000VA.

Offline/Standby/Battery Backup

Offline UPS, also called standby UPS or battery backup, is a cost-effective choice. Better offline UPS systems switch to battery fast enough to prevent power anomalies and ride out short outages. An offline UPS protects against most spikes, but doesn’t maintain perfect power during minor sags and surges.

The key to offline UPS quality is the range of power the unit will except before switching to battery backup. The wider the range, the less drain on the battery and the more backup time available when the power shuts off. The more times the UPS switches to battery backup, the shorter the battery life.

Offline UPS technology will protect from most power spikes by clamping down on excess voltage and help ride out more than 90% of all outages. An offline UPS system passes utility AC power straight through the unit, past a transfer switch, to the output point where the protected load is connected .

When an input power failure happens, the built-in battery and the inverter, which converts the battery’s DC power to AC, are activated and connected to the output by the transfer switch. There is generally about a 6-8 millisecond break in power when transferring to battery back-up.

This technology is best suited for devices under 1500VA such as small offices, personal home computers and other less critical applications. Offline UPS is a good option for those requiring lower power capacity and cost. Offline UPS technology provides power backup protection for desktop equipment, gaming consoles, workstations, wireless networks and other electronics. During power outage, it provides enough runtime to save work in process and complete an orderly shutdown of equipment. In addition to power backup, most offline UPS systems offers basic surge protection as well.

The correct battery selection is necessary to ensure the required battery life of the UPS. When calculating the battery capacity, the following parameters are taken into account:

  • The power consumed by the load in kW or kVA. In the second case, you need to enter the output power factor.
  • Minimum battery depth in volts per battery cell. As a rule, the UPS sets a discharge level of 1.7 V per cell. When the voltage drops below this level, the UPS shuts down to protect the batteries from overdischarge.
  • The voltage on the DC bus or the number of 12-volt batteries serially connected in one group.
  • Required battery life for the specified power consumption.

The listed parameters are sufficient for selecting uninterruptible power supply batteries. Using a calculator to select UPS batteries allows you to reduce the time to select the optimal solution for a given battery life.

Parus Electro
  • About company Where to buy?
  • Dealer Program –>
  • Our production
  • Contact Us
Warranty & Service
  • Warranty terms
  • UPS installation rules
  • Maintenance
  • Service & Support
  • Battery selection online
    Где купить? –>
  • Information support
  • Download catalogs
  • Site Map
Contact Us

Official website of the company: © Parus Electro, 2011-2020

All information published on the website is for guidance only and under no circumstances is a public offer determined by the provisions of Article 437.

Seven years ago a friend gave me a Liebert PowerSure 250 UPS and it has done well for whatever (home) PC and monitor I’ve plugged into it over the years. I’ve just ordered a new PC with the Intel core i7-920 and other nice specs for 3 HDDs, a nice graphics card etc, and opted for a 700W power supply.

I’m guessing the new workstation will use a lot more power than my current Shuttle box (this will be a development machine running SQL Server). I found a UPS selector wizard which suggested I should choose a UPS capable of providing 524VA – my current UPS is only capable of 250VA.

I’ve read good reviews for an APC Back-UPS ES 700VA – which is 700VA, but it’s output capacity is only 405 Watts. Does that mean the 700W power supply in my new PC is over-spec’ed? Or have I missed something? I only want the UPS to run for 5 minutes in the event of a power-cut. How do you choose a UPS to cover your power requirements?

4 Answers 4

  • APC UPS Selector
  • Newegg PSU Wattage Calculator

Obviously, these tools are made by people who stand to make extra profits by skewing the numbers, but I have found they are pretty decent to work with.

How to select an uninterruptible power supply (ups) for your computer

As a very rough rule of thumb, the wattage rating of a UPS is approximately 0.6 * its VA rating so, as you have seen, a 700VA UPS is good for a power load of around (0.6 * 700) = 420W (your specs said 405W). Conversely, the minimum VA rating you need is approximately 1.6 * load wattage.

Your 700W PSU gives you some idea of how much power your PC will need ‘fully loaded’, but under normal running conditions it will perhaps use less than half this amount – it’s hard to tell without knowing the full specs. And don’t forget to add the wattage of your display if you want that to be powered by the UPS too.

Once you have worked out the maximum wattage of your load (the PC, possibly + display), you can choose the base VA rating of UPS you need – then you look at the specs and see which model suits your need. Here’s where the fun starts, because you next have to look at how long you want the UPS to run when the power goes – and this can take two paths.

You can pick a UPS that is rated for pretty much the full VA you need so it will be running at 100% of capability and will thus last ‘n’ minutes.

You can pick a UPS that is rated at a much higher VA value than you really need so, for example, is running at 50% of capability and will thus last for longer than the UPS from option 1.

To complicate matters, you can sometimes buy extra battery packs for use with an ‘option 1’ UPS so its VA rating is not increased but it will run for longer.

. or you can overspec as per option 2 and know that you can add to the load on the UPS in the future, albeit at the expense of run time.

This is the point where you decide whether to read up on all this and become a UPS choosing guru, or use the manufacturer’s UPS selection tools!

Some new information for an old thread. Your UPS should be capable of providing the max potential draw of your PSU. I mean, the entire point of the UPS is to protect your data so it should not be the weak link in the chain of components. Also, the price jump to a higher rated UPS isn’t that much in the scheme of things.

Another important thing to consider when choosing a UPS is whether your PSU has active power factor correction. These active PFC PSUs are more demanding of their input and can shut down when the UPS kicks on in a power outage. The quick reason – consumer UPSs typically output a squared sine wave approximation and an active PFC supply expects a smooth sine wave. When switching to a stepped wave, they might see a zero power state and just shut off. Not always, maybe sometimes, maybe never depending on the sensitivity of the components. More info on this thread.

As applies specifically to this thread and wattage ratings, a PSU with active power factor correction may actually draw more power when necessary to correct for misaligned current. This is possible anytime as power delivery is never perfect, but much more likely when the current is riding a squared off wave. So while you certainly need to provide for the power demand of all your components, you may need more headroom than you expect if your PSU overdraws to compensate for the output of your UPS.

Better to be safe. Get a UPS that meets or exceeds the wattage of the PSU. Also, buy a UPS that can safely operate with active PFC PSUs (which means the UPS delivers a pure or at least better-than-square wave).

(Uninterruptible Power Supply) A device that provides battery backup when the electrical power fails or drops to an unacceptable voltage level. Small UPS systems provide power for a few minutes; enough to power down the computer in an orderly manner, while larger systems have enough battery for several hours. In mission critical datacenters, UPS systems are used for just a few minutes until electrical generators take over.

UPS systems can be set up to alert file servers to shut down in an orderly manner when an outage has occurred, and the batteries are running out.

Surge Suppression and Voltage Regulation
A surge protector filters out surges and spikes, and a voltage regulator maintains uniform voltage during a brownout, but a UPS keeps a computer running when there is no electrical power. UPS systems typically provide surge suppression and may provide voltage regulation. See surge suppression.

Standby and Line Interactive
A standby UPS, also called an “offline UPS,” is the most common type of UPS found in a computer or office supply store. It draws current from the AC outlet and switches to battery within a few milliseconds after detecting a power failure.

The line interactive UPS “interacts” with the AC power line to smooth out the waveforms and correct the rise and fall of the voltage.

Online UPS
The online UPS is the most advanced and most costly UPS. The inverter is continuously providing clean power from the battery, and the computer equipment is never receiving power directly from the AC outlet. However, online units contain cooling fans, which do make noise and may require some location planning for the home user or small office.

How to select an uninterruptible power supply (ups) for your computer

We often experience frequent power failures that not only perturbs us but also causes hindrance to a work in progress on our computers. If multiple applications are running and the computer suddenly becomes non-operational due to a power outage, then it is not only harmful to the device but can also lead to data loss and huge downtime. However, by installing an Uninterruptible Power Supply (UPS), a device that provides backup power to a device connected to it when the main power source fails, we can remedy the situation easily. A UPS provides electrical energy for a short time to allow the user to shut down the computer in a safe and proper way, avoiding possible internal damage of the system.

Moreover, a desktop uninterruptible power supply provides protection from power source electrical surges and spikes. It intercepts the surge and provides filtered and clean power so that the computer is not damaged, internally.

How to Choose Desktop Uninterruptible Power Supply?

Here are some of the factors which you need to consider while choosing the right desktop uninterruptible power supply.

1. Power Capacity of the UPS System

While purchasing an Uninterruptible Power Supply, one of the foremost things that needs to be considered is the amount of power this backup power device delivers. The UPS must be capable to supply adequate power that matches the required electrical load of your desktop units (monitor, CPU, keyboard) to keep your computer running and give ample time to save important work and to shut down your computer safely. If you buy a UPS in accordance with the power requirement of your desktop system, then it will effectively provide your device with unrestricted power during an electrical disruption.

The Central Processing Unit (CPU) is the component that needs most of the power supply to function. However, the monitor and other supplementary devices plugged into the CPU can function at lower power.

2. Runtime of the UPS System

Runtime denotes the amount of time the UPS is capable of providing backup power supply to the device connected to it during power outages. It is recommended to choose an Uninterruptible Power Supply device, which has an output watt capacity 20 to 25 percent higher than the total wattage of the desktop unit, including the monitor, CPU, keyboard, and the mouse. You can use a UPS watts calculator to measure the total load before opting for a UPS system.

3. The Type of UPS System You Need

There are basically three types of uninterruptible power supply systems, namely, standby, line interactive, and dual conversion UPS systems.
The standby UPS uses its battery power only when the voltage goes below a certain point, like below 90 volts or completely diminishes. This UPS system is the least expensive one.

The second category of UPS is the line interactive UPS system, which comes with an inbuilt transformer. , and mainly utilized when the Alternating Current (AC) voltage becomes too low or too high, this UPS system uses the transformer to balance the voltage by bringing the voltage back within the target limit when the power voltage drops drastically. A line interactive UPS only uses its reserved battery power during the complete absence of electrical power on the main grid.

The third type of uninterruptible power supply is the dual conversion system, which changes Alternative Current (AC) power into Direct Current (DC) and then again transforms it into AC. This type of UPS must be chosen only if your area faces a lot of interruptions, micro-outages, or sags in the main power line or if your equipment requires sine-wave power.

4. Functions that the UPS Needs to Perform

When you select the type of desktop uninterruptible power supply system, determine whether all the devices connected to your computer are required to function during a power outage or surge. For instance, if you think that you can work without the use of the scanner, speakers, and printer until the main power supply is restored, then you can select a smaller and cheap UPS as a means of your backup power supply.

5. Number of Outlets a UPS System Has

Another vital factor to consider while choosing a desktop uninterruptible power supply is the number of outlets or ports that have been built into it. Most of our desktop workstations consist of more than the monitor connected to the CPU. There are various additional electronic item present such as speakers, printers, wireless routers, a fax machine that is connected and synced to the computer. Therefore, all these additional devices also need to be connected to the uninterruptible power supply system so as to avoid sudden shutdowns during power outages.

All UPSs’ come with outlets. However, the number can vary from one UPS system to another. As a customer, it depends on you as to how many outlets you need in A UPS system. Once you determine the number purchase a UPS system that fulfills your requirement.

In Conclusion

Thus, for installing the appropriate desktop uninterruptible power supply you need to consider the aforementioned aspects to make the right choice. A UPS ensures that your productivity won’t suffer during any power outage allowing you to prevent downtime and work without disruptions. It also saves you from lengthy recovery time of your computer and also the need to feed data repeatedly in case there is power disruption. Thus, for its multifarious advantages, you must install a UPS system for your desktop without any fail.

Laptop UPS Runtime Calculator. Choose the Best Battery Backup

As we rely more on our computers or laptops for work and study, it is crucial that we have the means to keep our devices powered on and connected. One popular gadget right now is the uninterruptible power supply (UPS).

The UPS is usually used by desktop computer owners as it gives them time to save their work in case of a power interruption. It also helps protect their computer setup in case of a power surge.

For laptop users, the use of UPS may seem redundant, since laptops have their own batteries and can stay powered on for hours. But laptop users can also benefit from using a UPS.

Some benefits of using UPS for laptops include:

  • Longer battery life during power outages
  • Protection against power surges and dips
  • Allows you to plug in additional devices even during an outage

In some cases, people prefer their laptops plugged into a power source with the battery removed. This may save their battery from early deterioration, but it can be problematic when there’s a sudden power outage. Using a UPS can save you from a lot of problems and headaches.

There are a lot of different types of UPS available in the market, but not all of them may be compatible with your laptop. You also have to consider how much power your laptop uses to determine the type of UPS you would need.

Table of Contents

Laptop UPS Runtime Calculator

Before clicking that buy button, first, you need to check the UPS runtime by using an uninterruptible power supply calculator.

But before that, you need to familiarize yourself with some terms that you need to check on the UPS and the laptop you will be plugging in.

Terms to remember

Battery capacity (AH) – ampere per hour is the measure of how much charge a battery can store; it can be seen on your laptop battery and on the UPS

VA Power Rating (VA) – VA or Volts*Amps is the maximum charge of the battery; it is the max power your UPS can hold

Watts Power Rating (W) – the actual power output of the UPS

Total load (Wt) – the sum of the power consumption of all the devices that will be plugged into the UPS

UPS runtime formula

To calculate the UPS runtime when using a laptop, you can use the following formulae:

Time = AH / A

Assuming you are using a laptop with a power draw of 60W, and it will be the only thing you’re plugging into your UPS, this will serve as your Wt. You will need a UPS with 100W or higher.

If you have a UPS with a 12V battery, a battery capacity of 2.9AH, and a Watts Power Rating of 300W, it can support the power demand of your laptop. The question now is, how much time do you have to put the battery pack back in your laptop so you won’t lose your work?

Formula 1: A = Wt/V

Formula 1: Time = AH/A

Time = 0.58 hours

For more context, you can convert hours to minutes by using this formula:

Formula 3: Minutes = Hours (60 minutes/1 hour)

Minutes = 0.58 hours (60 minutes/1 hour)

Minutes = 34.8 minutes

Based on the calculations above, the UPS will keep your laptop powered for 34.8 minutes. It will give you enough time to save your work.

UPS runtime calculator

Calculating how long a UPS will last can be a tedious task for some, plus in some cases, all the data you need are not readily available, which means more computation will be needed.

APC UPS runtime tool

The American Power Conversion Corporation or APC offers a runtime tool to help you select which UPS to get. In APC’s UPS selector , you just need to know the power draw of your device.

For laptop users, choose Home, Home Office and Small Business then click Configure by Device. Next, choose PC/Laptop from the selection provided.

Select the model and quantity of the devices you are going to use the UPS for. Choose Unlisted if the model or device is not on the list. In this case, select 1 for the quantity since you’ll only be using it for a laptop. Input the power draw of your laptop, which in the example above is 60W.

Click add. It will then tell you the voltage of the UPS you need. In this case, a UPS with a 230V will be sufficient. Click Continue.

APC will then show you a list of UPS with their runtimes based on the parameters you submitted. The higher the VA, the longer the UPS lasts.

Best selling UPS

No products found.

One of the top-rated UPS is the No products found. that has a backup battery and surge protector. It has a total of 10 outlets, 5 of which have surge protection and battery backup, while the other 5 only offer surge protection.

If you plug in a device with a power draw of 100W, the runtime for the APC UPS 1500VA is 1 hour and 8 minutes. It has an LCD display that helps you see how much power you have left before the UPS shuts down.

No products found.

Another highly rated UPS is the No products found. . It has 12 outlets, 6 outlets with surge protection and battery backup, and 6 outlets with only surge protection.

The 15000VA/900W battery can handle a single laptop plugged in but if it’s fully loaded, the runtime is 3 minutes. If only half the load is plugged in, this UPS can last for 12 minutes.

No products found.

The No products found. is a UPS that features a 1500VA/900W battery. If you plug in a 75W device, it can keep it on for 90 minutes. If you plug devices that total 450W, it can last up to 10 minutes.

It has a total of 10 outlets, 5 with backup power and surge protection, and 5 with only surge protection.


Power outages or power fluctuations can damage our electronic devices or worse, make us lose our work. To prevent this, the use of an uninterruptible power source has grown in popularity even with laptop users.

Make sure you choose the right UPS, taking note of the total load you will plugin before making a purchase. Just remember, UPS are not meant to power up your devices for hours, but give you time to power down your devices properly and protect against power surges.

How to select an uninterruptible power supply (ups) for your computer

A UPS stands for uninterruptible power supply and is equipment which is most necessary for your computer system to run. It provides constant amount of power to the system in case of power fluctuations or power loss. The UPS supplies lower to the system from built in batteries and converts direct current battery voltage into alternating current voltage. If you are someone who is planning to buy a computer anytime soon then you will also need to purchase a UPS. The following are some points which will help you choose UPS for your computer:

1. Decide the type of UPS you want

The first step to choose UPS for your computer is to decide the type of UPS which would be most suitable for you. There are two main types of UPS and they are online UPS and standby UPS. An online UPS is connected between the main power and the computer. It supplies power to your computer and provides power conditioning. This means it prevents spikes, sags, noises and surges. On the other hand, a standby UPS is one which either provides main power or its own power to the computer, depending upon which is available at that time. It shifts between both depending upon the requirement.

2. Make sure the UPS is loaded with features

When buying or choosing a UPS for your computer, make sure you get one which has the maximum features. These days, there is no end to the number of UPS options available in the market. While some come with remote control over the functionality, others support missions critical equipment etc. So make sure when you buy, you enquire about the various features and functionalities and get the one with the maximum for your own benefit. However do not overspend if the features aren’t of much use to you.

3. Do not forget your budget

When choosing a UPS, you must set a budget for it in advance. Since there is no end to the price of UPS devices, you must be restricted in your budget so that you don’t overstep it and spend more than you can afford to.

4. Check the warranty

You also need to see the warranty that is being offered to you. The more the warranty the better will it be for you. So do pay attention to the warranty of different UPS devices. Warranty must cover damages of various types as only then will it be useful to you.

How to select an uninterruptible power supply (ups) for your computer

Image Credits: Wikimedia Commons

5. Check whether the UPS comes with a rack or rack enclosures

These days, some UPS devices come with racks or rack enclosures. It is better to get one of this kind as it stays more protected from dust, water and other kinds of damages.

If you are someone who is facing some issue with UPS installation, then you must seek professional help immediately. For any computer hardware repair, you can contact Mr Right.

Sales & Technical Support Services of Uninterruptible Power Systems

When choosing a UPS system, it’s natural to focus on its functional and performance specifications, such as UPS battery autonomy, availability, capacity, and energy efficiency. While these aspects are essential, there’s also another critical success factor; the UPS installation environment.

To ensure long-term reliable operation it is essential to select the proper uninterruptible power supply (UPS) for use in the correct temperature and environments.

To make sure of the appropriate UPS solution, we recommend to always check its operational temperature specifications and ensure that it meets or exceeds the environmental conditions when planning for a UPS installation at the site you have chosen. It is recommended that the uninterruptible power supplies be installed in a temperature controlled environment similar to the intended applications of UPS systems.

An uninterruptible power supply should not be placed near other heat sources or near open windows or areas that contain high amounts of moisture; and the environment should be free of excessive dust and corrosive fumes. In addition, the ventilation openings at the front, side or rear of the unit must not be blocked.

Ambient Temperature

All uninterruptible power supply batteries have a rated capacity which is determined based on specified conditions. The rated capacity of UPS batteries is based on an ambient temperature of 20°C or 25°C. Operating an uninterruptible power supply under these conditions will maximize the life of the UPS battery and result in optimal performance. We recommend a running temperature of 20°C to achieve expected service life. While a UPS system and the battery will continue to operate in varying temperatures, it is important to note that this will likely result in diminishing the performance and a reduced lifespan of the UPS battery. A general rule to remember is that for every 10°C above the ambient temperature of 20°C the life of uninterruptible power supply batteries will be reduced by 50 percent. Therefore, keeping UPS batteries at a comfortable temperature is crucial to maximizing UPS life span and capabilities.

In many cases, a UPS system is designed for use in the stated temperature environment, so internal components near their temperature limits could exceed their maximum temperature ratings. This could result in the UPS solution having a reduced reliability and life span, or an outright failure.

Designing adequate cooling for the UPS room will ensure the reliability of the uninterruptible power supply equipment itself. If your air conditioning is working but inefficiently, it will not produce a sufficient volume of chilled air and will lead to the UPS system overheating. This is typically noticeable during hot summer days. You will need to check that you have enough air conditioning units and that they are all serviced regularly to provide the correct amount of cooling for the designated UPS installation.

With larger industrial uninterruptible power supply solutions it may be worth considering a separate battery room to allow the UPS batteries to be kept at the optimal temperature while allowing the UPS room to have wider temperature tolerances.

How to select an uninterruptible power supply (ups) for your computer

Lithium ion battery cabinet

Conditioned free cooling

Any amount of cooling you can get at no charge will conserve energy and save you money. With so much energy being consumed by UPS power supplies, heat quickly builds up and cooling it all has become an expensive necessity in order to protect UPS systems from failure.

The first thing to know about free cooling is that it harnesses a free element – outside air. The most direct way to use this air to cool your UPS room is to fit vents or windows that you can open on a cold day. That’s how the principle of free cooling was first born, but today’s free cooling UPS solutions are significantly more sophisticated and energy efficient.

Letting cold air in and warm air out is a sound enough principle, but a rudimentary ventilation system is never going to bring cooling to the parts of the data centre infrastructure that need it most. Letting the outside into your uninterruptible power supply room also presents a series of environmental and security risks that could have catastrophic consequences. A vent could let cold air in, but also dirt, insects or birds and there is a very real risk of condensation building up. This is among the reasons why water is piped into data centre environments as the heat exchange medium for free cooling systems. The feasibility for free cooling rests upon the ambient temperature being sufficiently low to deliver additional, incremental benefit to the conventional cooling operation.

It should go without saying that there are many significant dangers associated with introducing water into highly controlled environment with sensitive IT equipment powered by large quantities of electricity. This explains the reasoning behind a professionally designed, manufactured and installed free cooling UPS solution, delivered and maintained by an expert UPS company using industry best practices.

When the power does go out

Start saving documents immediately (definitely do this ASAP if you’ve been bad and ignoring those pop-ups about replacing your UPS battery). Better safe than sorry.

Wait a minute or so in case it’s just a brief outage.

Close applications and logout.

After a period of time, depending on the estimated battery life of your UPS, the UPS/computer should initiate an automated shutdown. But, no harm shutting it down manually. Wait until the login screen appears, press Ctrl-Alt-Del, select Shutdown, Shutdown again and wait until the computer powers off.

Wait until the computer completes the shutdown and powers itself down. Once the computer is off, press the power button on the UPS which will stop it from beeping during the remainder of the power outage.

  • Flip the power switch on any printers, scanners, etc. to the Off position to prevent them from powering on immediately when the power returns.
  • When the power returns

    Don’t power things up right away. Wait at least 10-15 minutes. Occassionally power outages come in a series depending on what’s causing it. More importantly, in the event of an extended power outage, it may be the case that the network and various servers went off-line and need to get back up to speed. This won’t happen instantly and will require time, so hold off on your temptation to be the first to get your computer running – you’ll only run into trouble.

    After 10-15 minutes, turn the power on on your UPS and wait 10-15 seconds until the On-line light on the UPS turns green.

    Turn on your computer.

  • Turn on monitors, printers, scanners, etc. If you forgot to turn off a network printer earlier, turn it off, wait 15 seconds and turn it back on again (this will ensure that it is talking to the network properly).
  • If your computer shutdown immediately or too soon.

    A UPS typically has “BATTERY BACKUP” outlets and “SURGE ONLY” outlets for you to plug in equipment. Only your computer and monitor should be plugged into the “BATTERY BACKUP” side – printers, scanners, speakers, etc should be connected to the “SURGE ONLY” side – this will extend uptime of the UPS/computer in the event of a power outage. It may be the case that your computer and/or monitor is plugged into a “surge only” outlet on the UPS in which case it would power off as soon as power was lost to your office.

    If may be the case your UPS battery is old and needs replacing. You can check the expected battery life by clicking the “APC Powerchute” icon in the bottom right of your tray near the clock in your taskbar. If the estimated battery life is less than 5 minutes, you definitely should replace the battery asap. Don’t ignore low battery warnings . A battery costs $39 – just send us the account to charge and a description of the research that the computer is being used for if it is being purchased off of a research grant.

    Perhaps there’s a problem with the UPS itself – just let us know and we can check it out.

    A simple way to confirm your estimated battery life is to power down your computer, restart it and while it is starting press F2 (or maybe DEL) to stop the boot process at the BIOS screen (don’t let it boot into Windows). Then, just pull the UPS plug from the wall and see how long the computer stays on before losing power.

  • Alternatively, just logout, and without powering down, when the computer is at the login screen, pull the UPS plug from wall. After several minutes your computer should do a controlled/automated shutdown and power off before the UPS itself loses power. If the UPS loses power power before the computer shutdown completes, you probably need a new UPS battery or possibly the UPS itself is faulty (just ask us to check it if you like).
  • A good UPS is definitely worth the money

    If you don’t have a UPS, the immediate lose of power can result in the lose of work, plus the harddisk can become corrupted which may result in a computer that won’t boot. If warnings come up indicating the battery needs to be replaced, don’t ignore those – let us know so we can get a new battery in place (batteries typically need to be replaced every 3-5 years or so and run about $39).

    A UPS is good insurance:

    • A UPS will give you a really happy feeling the first time the power goes off and you’re able to continue to work in the dark and save stuff in progress that would otherwise be lost. At this point you realize that it has paid for itself.
    • A UPS will save potential downtime from hard disk corruption which may require the OS to be reinstalled. Depending on our current workload, you may be without the computer for several days.

    BTW, even if you don’t value your own time and have unlimited funds, do us a favour and make sure you have a good UPS and battery on your computer so we don’t have to spend time attempting to recover unsaved work (best we’ll be able to do it go to a previous backup) and rebuilding your damaged machine. Thanks.