[GMCnet] ground and neutral tied together [message #187900] |
Sun, 21 October 2012 20:13 |
rallymaster
Messages: 662 Registered: February 2004 Location: North Plains, ORYGUN
Karma: -4
|
Senior Member |
|
|
Where is it that the ground and neutral are not supposed to be tied
together in our coaches?
Water heater? breaker box? I was connected to a GFCI, and it kept
popping.
ronC
Ron & Linda Clark
1978 Eleganza II
North Plains, ORYGUN
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ron & Linda Clark
North Plains, ORYGUN
78 Eleganza II
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187905 is a reply to message #187900] |
Sun, 21 October 2012 20:51 |
|
mike miller
Messages: 3576 Registered: February 2004 Location: Hillsboro, Oregon
Karma: 0
|
Senior Member |
|
|
rallymaster wrote on Sun, 21 October 2012 18:13 |
Where is it that the ground and neutral are not supposed to be tied together in our coaches?
Water heater? breaker box? I was connected to a GFCI, and it kept
popping.
|
General rule:
Ground and neutral should NOT be tied together except at "the source."
For motorhomes, that would be ONLY at the generator.
Yes that means the shore line ground and neutral are kept separate. (They are connected somewhere upstream... )
Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo'
http://m000035.blogspot.com
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187906 is a reply to message #187900] |
Sun, 21 October 2012 21:30 |
GeorgeRud
Messages: 1380 Registered: February 2007 Location: Chicago, IL
Karma: 0
|
Senior Member |
|
|
They absolutely need to be kept separated. There was a nice article in the FMCA monthly magazine a year or so ago that went through the reasons quite well.
As said, they only should be connected at the generator or at the circuit breaker box if plugged in.
George Rudawsky
Chicago, IL
75 Palm Beach
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187908 is a reply to message #187900] |
Sun, 21 October 2012 21:29 |
rallymaster
Messages: 662 Registered: February 2004 Location: North Plains, ORYGUN
Karma: -4
|
Senior Member |
|
|
Any suggestions as to where to start looking, Mike?
I seem to remember a thread somewhere on the subject, but what I found on
the Forum wasn't of any use.
gmcmotorhome.com search didn't reward me with sudden insight.
Just found Gene's other site with Duane Simmons' GFCI trouble-shooting
guide. Maybe I can find the problem, now.
ronC
On Sun, 21 Oct 2012 20:51:33 -0500 Mike Miller <m000035@gmail.com>
writes:
>
>
> rallymaster wrote on Sun, 21 October 2012 18:13
> > Where is it that the ground and neutral are not supposed to be
> tied together in our coaches?
> >
> > Water heater? breaker box? I was connected to a GFCI, and it kept
> > popping.
>
>
> General rule:
>
> Ground and neutral should NOT be tied together except at "the
> source."
>
> For motorhomes, that would be ONLY at the generator.
>
> Yes that means the shore line ground and neutral are kept separate.
> (They are connected somewhere upstream... )
> --
> Mike Miller -- Hillsboro, OR -- on the Black list
> (#1)'73 26' exPainted D. -- (#2)`78 23' Birchaven Rear Bath --
> (#3)`77 23' Birchaven Side Bath
> http://m000035.blogspot.com
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
Ron & Linda Clark
1978 Eleganza II
North Plains, ORYGUN
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ron & Linda Clark
North Plains, ORYGUN
78 Eleganza II
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187912 is a reply to message #187908] |
Sun, 21 October 2012 22:09 |
Ken Burton
Messages: 10030 Registered: January 2004 Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
I do not understand your second posting. Two people replied correctly that the neutral and ground are not connected together in the coach anywhere.
The neutral and ground are only connected together at the power source.
In the case of shore power that connection will be at the secondary of the power transformer (the source of your power) ONLY. If you are running on the Onan that connection will be at the Onan before any switching device or before the OEM plug on the wall.
I think what is confusing you is that you are try to equate your coach to a residential power source. In a home that connection is usually at the meter box or the main breaker panel. The power box in your GMC is not the main power panel. The main power or breaker panel is in the Onan or back in the shore power supply.
DO NOT connect the neutral together anywhere in your GMC.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187918 is a reply to message #187908] |
Sun, 21 October 2012 22:34 |
|
mike miller
Messages: 3576 Registered: February 2004 Location: Hillsboro, Oregon
Karma: 0
|
Senior Member |
|
|
rallymaster wrote on Sun, 21 October 2012 19:29 |
> rallymaster wrote on Sun, 21 October 2012 18:13
> > Where is it that the ground and neutral are not supposed to be
> tied together in our coaches?
> >
> > Water heater? breaker box? I was connected to a GFCI, and it kept
> > popping.
On Sun, 21 Oct 2012 20:51:33 -0500 Mike Miller <m000035@gmail.com>
writes:
>
> General rule:
>
> Ground and neutral should NOT be tied together except at "the
> source."
>
> For motorhomes, that would be ONLY at the generator.
>
> Yes that means the shore line ground and neutral are kept separate.
> (They are connected somewhere upstream... )
Any suggestions as to where to start looking, Mike?
I seem to remember a thread somewhere on the subject, but what I found on the Forum wasn't of any use.
gmcmotorhome.com search didn't reward me with sudden insight.
Just found Gene's other site with Duane Simmons' GFCI trouble-shooting guide. Maybe I can find the problem, now.
|
The cause of the GFI tripping could be almost anything in the coach. but mostly I would suspect the water heater.
GFI's trip when the current on the current neutral side does not match the current in the hot leg. Most likely a current leak to somewhere... hopefully the ground, not you!
Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo'
http://m000035.blogspot.com
|
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187923 is a reply to message #187917] |
Sun, 21 October 2012 22:41 |
midlf
Messages: 2212 Registered: July 2007 Location: SE Wisc. (Palmyra)
Karma: 1
|
Senior Member |
|
|
This document gives a step by step process, with pictures, of how to check out the safety of the GMCMH 120VAC electrical system. Give it a look see and determine if it seems to address your GFCI tripping problem. Ask questions here if you have any or have a problem following the proceedure or have questions on followup.
Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187957 is a reply to message #187900] |
Mon, 22 October 2012 09:34 |
kingd
Messages: 592 Registered: June 2004
Karma: 2
|
Senior Member |
|
|
I think it is the latest issue of Motorhome magazine has a tech article on checking electrics in a motorhome. Including words about "hot skin". Like when you get a shock while touching the coach and the ground(soil) with conductive footwear at the same time.
DAVE KING
lurker, wannabe
Toronto, Ontario, Canada
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187968 is a reply to message #187900] |
Mon, 22 October 2012 11:08 |
lqqkatjon
Messages: 2324 Registered: October 2010 Location: St. Cloud, MN
Karma: 5
|
Senior Member |
|
|
just from my experience:
found a outlet badly corroded. most all of my stuff looked fine. but finally found the issue with the outlet.
changing that stopped my gfi popping problems. so for good measure, I installed all new outlets. I think cost me $10, and did it all in an hour.
before digging too far, it is pretty easy to pull the plates of the 5 or so outlets, to make sure they are all looking good.
there is not too many pieces of the 120 system, where you should be able to check that all the wiring looks in decent shape.
Jon Roche
75 palm beach
EBL EFI, manny headers, Micro Level, rebuilt most of coach now.
St. Cloud, MN
http://lqqkatjon.blogspot.com/
|
|
|
|
Re: [GMCnet] ground and neutral tied together [message #187976 is a reply to message #187918] |
Mon, 22 October 2012 12:09 |
|
mike miller
Messages: 3576 Registered: February 2004 Location: Hillsboro, Oregon
Karma: 0
|
Senior Member |
|
|
Mike Miller wrote on Sun, 21 October 2012 20:34 | ...
The cause of the GFI tripping could be almost anything in the coach. but mostly I would suspect the water heater. ...
|
Duh!
Flip off all the breakers in the coach and check if the GFI still trips.
Then flip on the "main" and check.
Then check one "output" breaker in the coach at a time. This should let you know what leg to look at.
It is also possible that the GFI of the outlet itself has the problem... (The one the whole coach is plugged into.) I have seen that, but it is unlikely.
Mike Miller -- Hillsboro, OR -- on the Black list
(#2)`78 23' Birchaven Rear Bath -- (#3)`77 23' Birchaven Side Bath
More Sidekicks than GMC's and a late model Malibu called 'Boo'
http://m000035.blogspot.com
|
|
|
Re: [GMCnet] ground and neutral tied together [message #188001 is a reply to message #187900] |
Mon, 22 October 2012 08:56 |
rallymaster
Messages: 662 Registered: February 2004 Location: North Plains, ORYGUN
Karma: -4
|
Senior Member |
|
|
Thanks to all who have responded.
====================
No, Ken, my poor choice of wording.
I'm trying to troubleshoot a GFCI problem. I was connected to a GFCI
source and it opened the circuit about a second after it was reset. I
guess my question should have been, "Where are the likely places that the
ground and neutral might be connected in the coach." I've heard that an
old water heater element is a likely source of a leak between ground and
neutral, but mine is only a few months old.
The little 3 neon tester gizmo says all is right with the world on all
the outlets I can find. I don't know if this is a new problem or an
ongoing problem, as I've never connected to a GCFI outlet before.
Thanks,
RonC
On Sun, 21 Oct 2012 22:09:53 -0500 Ken Burton <n9cv@comcast.net> writes:
>
>
> I do not understand your second posting. Two people replied
> correctly that the neutral and ground are not connected together in
> the coach anywhere.
>
> The neutral and ground are only connected together at the power
> source.
>
> In the case of shore power that connection will be at the secondary
> of the power transformer (the source of your power) ONLY. If you
> are running on the Onan that connection will be at the Onan before
> any switching device or before the OEM plug on the wall.
>
> I think what is confusing you is that you are try to equate your
> coach to a residential power source. In a home that connection is
> usually at the meter box or the main breaker panel. The power box
> in your GMC is not the main power panel. The main power or breaker
> panel is in the Onan or back in the shore power supply.
>
> DO NOT connect the neutral together anywhere in your GMC.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
Ron & Linda Clark
1978 Eleganza II
North Plains, ORYGUN
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
Ron & Linda Clark
North Plains, ORYGUN
78 Eleganza II
|
|
|
|
Re: [GMCnet] ground and neutral tied together [message #188003 is a reply to message #187900] |
Mon, 22 October 2012 16:59 |
|
RF_Burns
Messages: 2277 Registered: June 2008 Location: S. Ontario, Canada
Karma: 3
|
Senior Member |
|
|
I should have added, you need to pull both the hot and the neutral from the water heater element (and insulate them) to eliminate the water heater element as the cause.
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC. 1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
|
|
|