ensures that the device continues functioning even if the primary source of electrical supply is not able to provide it with the power to function. This is very important to improve efficiencies of workplace environments that rely largely on electric supply, such as an office that uses computers.
Different Types of Uninterruptible Power Supply
There are three main types of UPS, based on their method of providing the power supply. These are as follows:-
Standby UPS, also known as the Offline UPS – The offline UPS is the most basic design of the UPS. It works in the following manner – As long as the external electrical supply is on, the UPS remains inactive, though it keeps on charging itself. However, if there is any ebb in the amount of power being supplied to the device, the UPS will take over and supply current. This it will continue until the primary power is back to normal. When that happens, the UPS will go back into its standby mode.
On-line UPS – The on-line UPS draws current from the main source of power, but supplies the power from its own battery to the device that is connected to it. In this manner, it delegates the main source of power to a secondary position and itself becomes the main source of power for the device. Such a UPS system will provide a continuous source of power to the device through its own battery, which is charged from the external source. In case the main power supply fails, the battery of the UPS keeps providing power to the device without as much as a blink. To understand this, recall the way your laptop works when it is connected to AC mains. As long as it is connected to the mains, it will draw power from there. But if you shut down that switch, the laptop will still remain functional, because then its internal battery takes over completely.
Line Interactive UPS – This is a modified form of the original UPS system in which there is a regulator to keep the current coming into the device at a steady flow. You can consider this as a normal standby UPS with a filter attached. Typically, this UPS functions by drawing some part of current from the AC mains to charge its own battery and use the rest of it to power the device attached. In case there's a power failure, the line connecting to the AC mains is switched off and the battery takes over in energizing the device.
What does an Uninterrupted Power Supply actually do?
The general perception is that an Uninterrupted Power Supply provides power to an electrical device in case there's a blackout, and that's the only function people attribute to it. But, the UPS performs several other functions. It not only powers the device when there's a power failure, but it can also keep the voltage difference across the device at a constant rate. That means, if there is an unexpected fall in the current flowing into the device or, for that matter, even an unexpected surge, the UPS will take care that the voltage difference across the device is still maintained constantly. For sensitive devices like computers and air conditioners, this is a very important benefit.
If you think by the principle of working, anything that provides an unhindered power supply to an electrical device can be called as an UPS. Indeed, some professionals even call the small 9 volt batteries that are used as backups for less power-consuming electrical devices as UPS systems. At the same time, UPS is also applied to heavy devices that are used in workplace environments and in residential buildings.