In a perfect world, your power will never disappear, or it can prevent your power from spreading. However, we are not living in a perfect world: we live in a world of power failures that do not have enough power and power lines. For some devices, these are not only annoying: accidental power outages can corrupt data on your computer or panic your home security system. If the power supply stops unexpectedly, medical equipment such as CPAP will eventually die of suffocation. So what can you do to protect your device from these issues? Install an uninterruptible power supply or UPS.

The job of the UPS is to provide continuous power to these critical devices, solve problems and provide backup power when the lights go out. They do this by placing a backup power source between the device and the power outlet and then constantly monitoring the current in the wall outlet and the device.

There are different types of UPSs, but those designed for computers and small devices are typically connected in series where the input power is converted from alternating current (AC) to direct current (DC) and then fed into the battery. At the same time, on the contrary, some of them are converted back to AC and then output to the device. If the power flowing into the device is interrupted, the battery will consume power and keep the current flowing. The powered device will never know the power outage.

Ok, as long as the battery lasts, it will never know. As long as the energy is stored in the car battery, the UPS can only keep the device powered. This is the Achilles heel of these devices and one of the main issues to consider when purchasing. The larger the battery, the longer the UPS can hold this current. But the bigger the battery, the bigger the UPS must withstand.

This energy stored in the UPS is measured at a voltage called volt-ampere (VA), which is the power transmitted over time. This determines how long the device connected to the UPS will last. The VA rating is usually associated with the watt rating and indicates how much power the UPS can provide at any time, which determines the number of devices the UPS can provide.


While it is difficult to determine a clear number of UPSs to ensure how long the equipment is running, many manufacturers offer basic UPS calculators. These allow you to enter the number and type of devices you want to back up and suggest products that may be suitable. If you want to know more, you can consult Daopulse.

How long UPS will last depends on the time you connect and the efficiency with which these connected devices use it. Some devices absorb power in an inefficient manner, so UPS can keep up with time, so they won't last long. This is called the power factor. Why this happens is very complicated, but as a general rule, the power factor of the equipment using the motor is very low, so you should not run equipment such as dishwashers and washing machines on small UPSs. The same is true for devices such as laser printers, which suddenly consume a lot of power (called inrush current) when they start up. The wall outlet has a good power supply, but the UPS cannot handle it, and some may be damaged by sudden power surges.

Most UPS also includes a USB port and software. When running on a PC connected to the UPS, it monitors the remaining charge and shuts down the computer when the battery is low. This clean shutdown will save your files and protect your data.

If you want to keep multiple computers running, you need a larger battery. The whole house UPS system is built into your power system and is usually located between the board that holds the fuse and the meter. When power is exhausted, they will intervene and keep power flowing through the house. There are several different types, such as line interaction and incremental conversion, which can handle the greater load of multiple devices that can be found in modern homes. However, these are major investments, so they are only needed where you have frequent power outages.