Answer / parmod kumar

it has the same two power sources, and a transfer switch
that selects between them. It is the exact opposite from
the standby UPS because it has reversed its sources: in the
online UPS the primary power source is the UPS's battery,
and utility power is the secondary power source!
Under normal operation the online UPS is always running off
the battery, using its inverter, while the line power runs
the battery charger.

why synchronization done in clockwise direction?

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why r use the wave taper in the substation ?

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