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7. Operation Modes
Uninterruptible Power Supplies (UPS) have an important function in the protection of the critical and sensi-
tive loads from the irregular mains electricity conditions and they are used to supply uninterruptible energy
to these loads. In such irregular mains electricity conditions, the user can provide an artificial energy supply
to the equipment present in the office or at home by using an UPS.
Keor S UPS during Inverter operation provides stable pure sine wave. This pure sine wave is not affected
from the input voltage fluctuations. This helps to extend the life time of your sensible loads. Power factor of
the current consumed from the mains is nearly one. You do not have any problem on generator or isolation
transformer applications. The reactive energy consumption decreases.
During the mains failure, the energy needed for the load is provided by the battery in UPS (or in external
battery cabinet/s). These batteries are charged by an intelligent battery charging circuit during the mains
within the limits. Batteries are lead acid battery (VRLA) and do not require any maintenance until the end
of their life time.
In case of longer overload or inverter failure situation, UPS transfers the load to Bypass line, and load is
supplied from the mains. When the condition turns back to normal, UPS shall continue to supply the load
through inverter.
UPS control and management is done by Digital Signal Processor (DSP) which is 200 times faster than stand-
ard microprocessors. This helps to make your UPS smarter. DSP uses all the sources on optimum conditions,
observes the failure conditions, and communicates with your computer system.
UPS can be operated in one of the following operational modes depending on the condition of mains, bat-
tery, bypass, UPS and/or user preference.
You may see the block diagram of UPS in Appendix-4 Description of UPS and Block Diagram.
