On Wed, 09 Jan 2008 00:03:42 -0500, Ned Simmons
wrote:

On Tue, 08 Jan 2008 17:04:05 -0500, Spehro Pefhany
wrote:

On Tue, 08 Jan 2008 16:08:56 -0500, Ned Simmons
wrote:


I don't have a clear enough picture of your equipment in all its
possible configurations to tell whether the NEC would consider it a
separately derived system. Is it portable? Is there an earth ground
other than thru the line cord?

Not really. It's in a moving vehicle.

The NEC does have a section on RVs, which even if not directly
applicable, may give some guidance.

Based on my understanding of the situation, I'd create a neutral by
bonding the common connection between the inverters to the vehicle's
chassis, and switch the neutral along with the hots when selecting
inverter or utility power.

I might reconsider if the inverter batteries can be charged by utility
power, and there isn't isolation somewhere between the utility input
to the charger and the inverters' outputs.

Inverters are running from a 300A generator on the vehicle power
system, and they provide input-output isolation.

Thanks, Ned, and everyone else who offered suggestions.


Best regards,
Spehro Pefhany
--
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