Date:         Thu, 26 Jul 2007 14:30:39 -0700
Reply-To:     neil N <musomuso@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         neil N <musomuso@GMAIL.COM>
Subject:      Re: Elec.Gurus! DC ground question (fridge fans off shore power)
Comments: To: Loren Busch <starwagen@gmail.com>
In-Reply-To:  <86476e250707261355o24b2d3e5g70f4af89defd499@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Thanks Loren.

The quality of the ground will be as good as the stock config allows.
(wire on stock 3 pt. connector to fridge)

I was just having a brain-phart as to whether there was some kind of
safety issue to sharing a common ground between 12V DC "shore power"
and "house power". In fact was having phart over whether it would work
or not...... but that was the lack of food "speaking".

Once I sat down and drawed myself a picture (schematic) of things, it
made sense. Obviously both power supplys can share the same ground.

i.e.

http://web.mac.com/tubaneil/iWeb/Site%205/FanCircuit.html

Pretty elementary, but staring at both the AC and DC on the top of the
fridge, kinda got my head bent....

Neil.


--
Neil Nicholson. 1981 Air Cooled Westfalia.

http://web.mac.com/tubaneil


On 7/26/07, Loren Busch <starwagen@gmail.com> wrote:
> RE: 12v Grounds for Accessories
> Some are going to argue that I'm overdoing it and that using chassis ground
> for accessories will work fine.  BUT, having had a really good education of
> grounds and ground loops back in the '60's (analog computers) I have a
> simple answer:  Run a separate ground for each circuit and ground everything
> at the same point.  I don't tap into any existing circuit if there is any
> way to avoid it, I run a double wire, hot and ground, to whatever I'm wiring
> in. All accessories added come out of a fuse block on the cabinet wall
> behind the drivers seat.  That is fed directly (through a 40 amp breaker)
> from the aux battery.  Right now I have a ground buss set up and mounted
> next to the fuse block, soom to be incorporated into a new, better fuse
> block that will replace the current setup.  In a previous life ('85 Westy)
> the PO had added two lights in the back, good halogen lights, plenty of
> illumination.  But, they worked sporadically and never when you really
> needed them.  When I got around to troubleshooting them the problem was
> grounds.  The DPO had assumed that he would get a good ground through the
> mounting screws that went into the body of the Vanagon.  Once those grounds
> were fixed no more problems.
>
>