Howard Eisenhauer
wibbled on Wednesday 24 February 2010 22:37

1st question- Is the existing wiring out to the barn up to the job?
i.e. how many amps is your genset capable of suplying- 60 amps through
#10 ain't gonna cut it.

2nd- how many amps is your service rated for & how many can the genset
supply? A 60 A feed into a 200A service means you're gonna be
manually flipping brakers off anyhow...

3rd- Is there a seperate main service dissconnect from your breker
panel? If not you'll have to add noe between the meter & panel if you
want the xfer swittch to feed th whole house

4th- how understanding is the carrier for your fire insurance?
Jerry-rigged transfer switches using non-approved parts aside if
there's any problems at all with *any* of your wiring (whether you
were the last one to touch that particular part or not) that causes a
fire you can probably kiss your coverage goodbye

Personally I'd go with a type approved manual transfer switch, with a
seperate feed coming to it from the generator, feeding a "essential
services" sub panel .



I second that. Not sure about the paranoia insurance, but what *is* very
important, is that the OP does not under any circumstances back feed into
the utility supply. Otherwise, in a power outage, some poor linesman up a
pole gets a live line he thought was dead.

The IEE Wiring regs in the UK have something to say about local sources (be
it generator, UPS) - does the USA NEC code have regulations on this too?
IIRC, the NEC is available for free online (we have to pay for a copy of the
IEE Regs) so there's no excuse for not reading them.

I personally would go for a "proper" transfer switch. It's not just about
switching over - it's about maintaining required levels of mutual isolation
(eg contact separation distances etc) too.

Don't forget issues of earthing too - in the UK, we cannot count on the
utility earth (ground) in such a case, we must provision a local earth rod
for local generation with all that entails (eg correct use of RCD/GFCI).

Cheers

Tim

--
Tim Watts

Managers, politicians and environmentalists: Nature's carbon buffer.