Date:         Fri, 10 Apr 2009 23:33:15 -0400
Reply-To:     pickle vanagon <greenvanagon@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         pickle vanagon <greenvanagon@GMAIL.COM>
Subject:      Re: gfci outlet buzzes with inverter
Comments: To: Ken Lewis <kdlewis@northstate.net>
In-Reply-To:  <001f01c9ba46$d0e02f80$0201a8c0@korky2>
Content-Type: text/plain; charset=ISO-8859-1

Hmmm... interesting.  I'm not sure I understand though, so bear with me.

The inverter is powered off the battery (obviously) and chassis ground.  It
powers an outlet whose ground (but not neutral) is also connected to the
chassis ground.

Are you saying that in this situation one can't be shocked by the outlet?  I
found some inverter manufactures discussing the use of GFCI outlets with
their inverters (for example see
http://www.xantrex.com/web/id/1193/DocServe.aspx).  I know some inverters
even come with GFCI protection built in.  What is the application where this
would matter if not in my case?

Thanks for any help understanding!

Another issue is that the same outlet runs off shore power sometimes (I use
a transfer switch) and it seems a good idea to have ground protection for
shore power, right?  I guess I could get a separate GFCI device and put it
just on the shore power line?

Or maybe I should abandon GFCI protection altogether?

Thanks again for any help!
Wes




On Fri, Apr 10, 2009 at 9:42 PM, Ken Lewis <kdlewis@northstate.net> wrote:

> Wes,
> I have to give this one a big ,"Hmmmmmm...". Isthe Inverter output isolated
> from (chassis) ground ?  If so the GFI is useless since there is not a
> current path through the body of the car back to the inverter. Logically,
> the inverter chassis would be at DC  ground potential and isolated from the
> AC output. AT least, that's the way I would design it. That way you couldn't
> get shocked standing wet and barefooted in your van making margaritas.
> Ken Lewis
> http://neksiwel.20m.com/
> in statu viae
>
>