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Old 12-06-2013, 06:55 PM   #22
jmsokol
New Member
 
Join Date: Dec 2013
Location: Hagerstown
Posts: 8
M.O.C. #13934
Quote:
quote:Originally posted by bncinwv

You should not have to use your external EMS with a Honda generator. If you elect to, you will have to do as described in various ways above. Easiest solution is simply not to use the EMS with your generators.
Bingo
I would say that statement is correct. Honda and Yamaha inverter generators are probably the cleanest and most stable AC power sources you can get outside of a dedicated utility line. And many times they will be BETTER than utility power. That being said, there's a lot of NON Honda and Yamaha generators with questionable AC power out there. Yes, these high-end Red and Blue generators are a lot more expensive than the cheap Chinese imports, but will provide many years of service.

So if you have an external EMS you could safely just leave it out of the generator connection when powered by a floated neutral generator. But, if you have a built-in EMS, you're stuck and need to provide a Ground-Neutral bond at the generator.

That all being said, I'm not really comfortable with running an RV from a floated neutral generator. At the very least you'll find that a 3-light cube tester will report an open ground. And if you have an appliance short its power connection to the frame, then your entire electrical system will be "flipped" with the hot at RV frame "ground" and the neutral at 120-volts above frame-ground potential. Not immediately dangerous, but hard to troubleshoot if something goes wrong and you're trying to measure voltages.

The given reason why these generators had a floated neutral to begin with is that when they're used to provide emergency backup power for a home via a transfer switch, the NEC doesn't want you to have two neutral-ground bonds, which would introduce neutral currents in the safety ground conductor. And an exception was made to the US code that would allow generators under 5KW to avoid the expense of a GFCI if the neutral was floated. However, just how many 2KW inverter generators are used to power an entire house through the service panel, compared to powering an RV? It's this sort of logic failure that makes the subject of generator neutral bonding so confusing.
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