AC dead short?

[Gardner Yeaw]

One way I was taught a loooong time ago to chase shorts in automobile wiring
harnesses was to connect it to a 12 volt source with a turn signal blinker
and a light bulb in series. Then follow the wire with an old boy scout
compass. When the wire is energized it forces the needle to move. You can
also use this method to locate wires. When the needle stops moving, you have
passed the short. I know there are more sophisticated tools today, but none
as cheap.

Gardner
78FC33

-----Original Message-----
From: WanderlodgeForum@yahoogroups.com
[mailto:WanderlodgeForum@yahoogroups.com]On Behalf Of one_dusty_hoot
Sent: Tuesday, August 22, 2006 6:25 PM
To: WanderlodgeForum@yahoogroups.com
Subject: [WanderlodgeForum] Re: AC dead short?

Tom, A polarity tester operates when voltage is
present. A dead short trips the breakers before
a reading could be made. Good for polarity testing,
not good for dead shorts.

A dead short is a ground on the line(s). The only way
I know how to find one is to isolate by disconnecting
sections of the system.

You say 2 circuits, vaccum cleaner and front receptacles
Are these tired together or seperate breakers? If
seperate breakers, try one then the other. Power off,
with a a multimeter on ohms position. Dead short is 0 ohms.
If not, Isolate and check everything. Sometimes the
load side of a breaker has more than one wire, to find
out, remove the front.

Bob Janes '87FC35 Greenville, SC

--- In WanderlodgeForum@yahoogroups.com
, Tom Warner
wrote:
>
> Get a cheap $5 polarity tester that you can insert in each wall
> receptacle and check for bad grounds etc. YOu should find the
problem
> quickly using it.
>
> tom warner
> 1985 PT 40....just like shanes
>
>
>
> At 01:01 PM 8/22/2006, you wrote:
> >Bill,
> >Is this the modification where we send the dinette control panel
to PMMI
> >for mods? How about the polarity tester lights in the shore power
> >connection panel, or does this get resolved by the modification to
the
> >dinette control panel?
> >
> >Curt Sprenger 1987 PT38, Anaheim Hills, Calif.
> >
> >
> >
> >pattypape wrote:
> >
> > >
> > >
> > > Is this a GFI protected pedestal outlet???
> > > Usually they are on the 15/20 amp park hook- up circuits.
> > > An old Bird will trip GFI if the polarity tester lights
> > > have not been modified.
> > >
> > > Bill 88 FC
> > >
> > > --- In WanderlodgeForum@yahoogroups.com

> > > , "John Ely"
> > > wrote:
> > > >
> > > > I have just developed a dead short in two circuits of my AC
> > > system.
> > > > The front receptacles and the vacuum cleaner circuits appear
to be
> > > > dead shorted. If they are on, the park circuit breaker (30
amps)
> > > > trips. If they are off, I get normal service from the park.
The
> > > > thing these two circuits have in common is the AC meters on
the
> > > > dinette control panel. The front receptacles circuit provides
> > > power
> > > > to one of the dinette AC meters while the vacuum cleaner
circuit
> > > > provides power to the other. I have removed all loads from
both
> > > of
> > > > these circuits with no change. I've pulled the cover from the
> > > breaker
> > > > box and these breakers have only one 12ga. wire going to
them, so
> > > the
> > > > meters must be wired in downstream somewhere, but I have no
idea
> > > where
> > > > or even where to look. As a possibly related matter, about two
> > > weeks
> > > > ago, after a lightning storm near Montreal, I noted that the
> > > polarity
> > > > indicators in my service box (the place where shore power is
> > > > connected) are no longer working. As there are also polarity
> > > > indicators on the dinette panel, there is a possible likage
here.
> > > > However, there was a two + week span of normality between the
loss
> > > of
> > > > polarity lights in the service box and the short circuits in
the
> > > AC
> > > > panel. No incident occurred prior to the AC loss; it worked
fine
> > > in
> > > > one park, we took a long (15 hour ferry ride) with the DC
systems
> > > shut
> > > > down, and had the shorts as soon as I plugged in at the next
park.
> > > > If anyone has any ideas as to what this might be, I'd be glad
to
> > > hear
> > > > them.
> > > > John Ely, 86PT40, Rapid City, SD On the road in Clarke's
Beach,
> > > > Newfoundland
> > > >
> > >
> > >
> >
> >
> >
> >
> >Yahoo! Groups Links
> >
> >
> >
> >
>



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