UPS

Admin May 23, 2019 0 Comments

What is a UPS

When there is a power surge or power failure, the UPS simply supplies power to the computer without interruption or shutdown.

The UPS is ideal for environments where electrical isolation is necessary or for equipment that is very sensitive to power fluctuations. When city power sags, outages and other anomalies are frequent, UPS provides advantages to sensitive IT equipment.

Many people believe that the only function of a UPS is to provide power in the event of a utility (power) failure. Power outages, even when load shedding is implemented, are not daily occurrences. Dips, surges, spikes and harmonics (dirty power) most certainly are. These unseen power disturbances can cause as many if not more problems than power failures. In the case of microprocessor based equipment, both hardware (equipment) failure as well as software (data corruption) failure are as a direct result of these unseen disturbances. A UPS, especially an online UPS will resolve the majority of these problems.

A UPS can be categorised into 3 main types:

  • OFFLINE OR STAND BY UPS

This is the most basic type of UPS and is used in areas where the utility power is fairly stable with the occasional outage (power failure). This UPS comprises of a battery charger, a battery and an inverter that has a square wave output. Utility mains feeds the load (computer etc.) directly until a power failure occurs. When a power failure occurs, the UPS inverter then switches on and produces a square wave output to feed the load.

  • LINE INERACTIVE UPS

This is a more sophisticated offline UPS. Some line interactive UPS have a sine wave output. In addition to the battery charger, battery and the inverter, this type of UPS has a built-in regulator to stabilise power fluctuations. It does not however, provide good regulation that certain electronic equipment requires, nor does it provide good input to output voltage isolation.

  • ONLINE UPS

Unlike the 2 types of UPS above, the inverter of this UPS is always running and feeding the load. The output of the inverter is a sine wave. The utility mains feeds the battery which keeps the batteries charged and the inverter running. In the event of an outage, the inverter keeps running, being powered by the batteries. The regulation of this type of UPS is excellent and the output is isolated from the UPS input. This is the ideal type of UPS to provide power to critical electronic equipment.