Wacky Weekend: NERC to relax power grid frequency strictures
alex at corp.nac.net
Sun Jun 26 09:27:24 CDT 2011
> It makes little sense to sync to the grid when the generator is only
> used when the grid is down - and unless you run your generators 24/7
> your UPS will have to make up for the comparatively long time it takes
> for the generator to start, so it's rather useless to sync the
> generator when the power comes back so you can avoid a sub-second break when
> transferring back to utility power.
No, that is precisely the reason to do closed transition. The benefit is no interruption to load on retransfer. Effectively, you cut down on UPS battery hits, motor restarts, etc, by 50%.
I, again, don't like this, because the cons, imho, outweigh the benefits.
More information about the NANOG