When the power goes out, how long will the computer turn off?

Desktop computers are dependent on power, not the battery that comes with laptops, so when the power goes out, the PC goes off. In fact, in your computer there is a PSU source device, capable of maintaining the stability of electricity for an extremely short time, only in milliseconds but it is very important for stability. of computer system.

This period of time is called the power-up time, or Hold Up Time. And according to Inte standards, this time must be greater than 16ms (or 16 milliseconds), equivalent to a sinusoidal cycle of the electrical frequency.

The computer source has the role of switching from alternating current in the network to a direct current. In the world, residential electric networks use two AC frequencies, 60Hz with a sinusoidal period of 16ms (equal to 1/60 of a second) and 50Hz (50Hz in Vietnam) with 20ms (equal to 1/50 of a second).

In unstable power grid areas, to ensure the maintenance of work, users often use extra power for computers. Meanwhile, when there is a power outage, short circuit, or overload or voltage drop, UPS units also need time to switch from using the alternating current of the network to using battery power.

Depending on the frequency of the electric network in the area, the UPS will be set the transition time: in the area using the power 50Hz is no more than 20ms and 16ms in the area using 60Hz electricity.

In order for the computer to remain active until the UPS battery is turned on when the power is turned off, Intel has requested that the computer power supplies meet the 16ms standard.

To ensure this standard it is necessary to use large capacitors to have enough capacity to maintain the computer operation and this affects the power of the power supply. As a result, many less-known source manufacturers sacrifice this parameter to lower the price of their equipment.

See more:

1. How to manually turn off the power light and hard drive light on the desktop
2. 5 things to know when buying computer power supplies
3. Computer power source: More important than you think