Forward and Reverse Synchronization

If you have 2 gensets, and the breaker on one set is closed, the other will be lagging the first if the speed is slower, or leading if the speed is faster. If you then try to synchronise, in the first instance, you will need to speed the genset up to synchronise. This is forward sync. If you need to slow the second gen down to sync, this is reverse.

It's highly recommended to stay away from reverse sync.

Thankyou

but what is the reason reverse synchronization is not recommended .i saw in the setting parameter parameters there is an enable\disable option .when shall we enable the reverse synchronization .for example if we have two gensets synchronized with automatic synchronizer and if we set one to be a master genset and the other one slave and when the sets take load the frequency of the master may be lower than the slave .does this mean that the slave genset will not synchronize its frequency with the master if we disable the reverse synchronization option

thankyou very much

i get what i realy want

GA for the article, Tomad.

For the original poster, I would add that the primary reason for synchronizing as the article describes is to prevent motorizing the generator. In forward synchronization, the oncoming source has a slightly higher frequency than the running source. When the breaker closes, the oncoming machine is locked into the same frequency. However, the higher governor setting ensures that the oncoming unit will carry some positive KW load. If the oncoming frequency were lower, when the breaker closed the oncoming machine would immediately become a load, absorbing power instead of producing it. It would quickly trip on reverse power.

If the generator is in service and the utility grid in oncoming, reverse synchronization is needed because the generator is usually a much smaller source. If the utility frequency were higher, it may pick up all the bus load and still motorize the generator, simply because of the utility's much larger capacity.

yes i think reverse synchronization is important in "no break mains return application" .this is an application where load is retransfered from the stand by generator to mains supply with out break when the main power(grid power) returns .most of the automatic synchronizers have this option.