How to choose a uninterruptible power supply: Which UPS select

The information in this article relates to a large number of diverse devices. Be sure to specify the characteristics before purchasing.

What are the UPS for computers represent?

There are various types of uninterrupted power systems. Offline UPSs are commonly used with home computers. They have batteries that are included in the loss of nutrition, and the uninterruptible itself is between power grid and protected equipment. It connects to the outlet, and the devices are connected to it.

Offline-UPS for computer equipment performs two main functions:

  • Adjusts an alternating voltage to reduce jumps that can damage the computer system.
  • For a short time, provides a computer with power when the electricity is turned off at home or in the office.

Most of the UPS is designed for electronics, in which there are only small unhindered motors - computers, audio equipment and televisions. Devices with large induction engines require specialized uninterruptible power sources.

If you are not sure whether to connect the device to the UPS, you can clarify this issue in support of the manufacturer of uninterrupted.

Power UPS

In order for the UPS to cope with its task, its power should be sufficient To power all connected devices. Before buying a uninterruptible, determine the power consumed by the whole technique that you plan to connect to it, and the time during which you need power when the electricity is disconnected.

Power consumption

Power that is necessary to ensure uninterruptible - a critical characteristic. It is measured in watts (W), one watt is defined as one Joule per second. For electrical engineering, power is equal to the product and current in the electrical circuit. In our case, the chain includes all the equipment connected to the UPS, that is, the system unit, monitor and periphery.

Almost all electronic devices indicate the necessary voltage, current and power consumption. To find the overall power of the system, fold it for all devices. If the power is not specified, multiply the voltage to the current - so you get the maximum power consumed by the device.

In addition, power consumed can be measured using special devices, for example, Kill A Watt.

Voltampear characteristics

Typically, the UPS manufacturers do not use power values ​​in watts. Instead, they use a voltampear characteristic - an estimate of the total power in the AC circuit. Since an alternating current is used to power computers and peripherals, a suitable method for measuring the real power consumption.

To calculate the required value of the voltampear characteristic in power there is a formula. The total power consumption of the system must be multiplied by 1.6. For example, if a computer and peripherals consume 800 watts, then the minimum value of the voltamper characteristic should be 1280 VA (800 W multiplied by 1.6). If rounded to the nearest standard value of the UPS streamer characteristic, then we will most likely need a 1,500 VA uninterrupted.

Opening hours

Opening hours - this time during which the UPS can provide Power supply system with the required power level when the electricity is disconnected. To calculate the time of operation, you will need a minimum voltampear characteristic, battery voltage, battery capacity and efficiency power sources.

These parameters are rarely specified by the manufacturer explicitly, but sometimes you can find them in the user manual or specifications. If you can accurately install them, the calculation can be carried out using a special online calculator.

If you can find the characteristics fail, go to the manufacturer's website and try to find the schedule of the time and load time ratio. There are also tools for selecting the UPS in accordance with your needs.

Find out the efficiency of the uninterrupted manner is usually the most difficult. If you can not determine it, you can take a value of 0.9 (90%) as a slight rough estimate.

An example of calculating the time of operation

in the uninterruptible power supply CyberPower CP1500AVRLCD uses 12-volt Battery Capacity 9 amp-hours, and efficiency is 90%. It can provide backup power to a computer system that consumes 1280 WA for 4.5 minutes.

At first glance, this is not much, but 4.5 minutes is enough to save data, close files and shut down the system. If you need more time, choose a UPS with higher efficiency, battery capacity, voltage, or a higher value for all of these parameters. A higher volt-ampere rating does not in itself provide longer operation, but most manufacturers install larger batteries in larger UPSs.

Replace the battery

The UPS battery has an average life of three to five years after which it needs to be replaced. Many uninterruptibles warn of the need for replacement, and some simply stop working. It is possible that during the period of operation of the UPS you will have to change the battery several times, so when choosing an uninterruptible power supply, it is useful to find out if there are replaceable batteries for it and how much they cost.

In addition, before buying, you should make sure that the UPS supports pass-through operation and can function as a surge protector in the event of a battery failure.