08-09-2009, 01:24 PM
read this bit
Modern microprocessor relays have the ability to look at closing rate and inhibit the
breaker closing if the rate is too fast. IOW, if the generators are at different
speeds and the phases are rotating past each other. They also have time delays,
anticipation capabilities and even the ability to generate a rate signal to go to the
governor. allows completely automatic syncing, no operator involved.
For small machines only the simplest relay would be
necessary. The relay would simply close the paralleling contactor
when the phase difference was within the window.
Modern microprocessor relays have the ability to look at closing rate and inhibit the
breaker closing if the rate is too fast. IOW, if the generators are at different
speeds and the phases are rotating past each other. They also have time delays,
anticipation capabilities and even the ability to generate a rate signal to go to the
governor. allows completely automatic syncing, no operator involved.
For small machines only the simplest relay would be
necessary. The relay would simply close the paralleling contactor
when the phase difference was within the window.
