| Chassis Voltage When hooked up to shore power [message #284067] |
Wed, 05 August 2015 18:54  |
Dan
Messages: 99
Registered: August 2014
Location: Allentown, NJ
Karma: 0
|
Member |
|
|
Hello,
Early this summer I blew a power steering hose while maneuvering into a site. As I messed with things I noticed that engine/chassis had some voltage. (It made my hands tingle). This seemed to stop if I unplugged from shore power. Is this normal? I am assuming this is AC voltage, anyone experience anything similar?
Dan DeLuca
1978 Eleganza II (http://imgur.com/gallery/YFHhK)
Parked at Evil Monkey Farm in
Allentown, New Jersey
|
|
|
|
| Re: [GMCnet] Chassis Voltage When hooked up to shore power [message #284070 is a reply to message #284067] |
Wed, 05 August 2015 19:27  |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
Daniel,
You're feeling leakage of the 120 vac from the shore power -- a potentially
dangerous situation. Before it's too late, download, study, and implement
the recommendations in Ken Burton's "Grounding the GMC Motorhome" at:
https://docs.google.com/viewer?url=http%3A%2F%2Fwww.gmceast.com%2Ftechnical%2FBurton_Grounding_GMC_Motorhome.pdf
or
https://goo.gl/MW1lcP
Ken H.
Americus, GA
'76 X-Birchaven w/Cad500/Howell EFI & EBL,
Manny Brakes & 1-Ton, etc., etc.
www.gmcwipersetc.com
On Wed, Aug 5, 2015 at 7:54 PM, Daniel DeLuca wrote:
> Hello,
>
> Early this summer I blew a power steering hose while maneuvering into a
> site. As I messed with things I noticed that engine/chassis had some
> voltage.
> (It made my hands tingle). This seemed to stop if I unplugged from shore
> power. Is this normal? I am assuming this is AC voltage, anyone
> experience anything similar?
>
>
> --
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284080 is a reply to message #284067] |
Wed, 05 August 2015 21:32 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
You need to find the problem promptly. In the shore power cable there is one conductor called a "green wire" of safety ground. The lead grounds your coach to the earth when plugged into shore power and prevents what you are talking about. That lead could be mis-wired or open in your coach or it could have been open or mis-wired in the shore power supply that you plugged into.
That said, other than a mis-wire situation in your coach, there is a possibility that you have something in the coach that is putting voltage on the chassis. The most common item that does this is the electric heating element in your water heater. If you can duplicate the failure, then disconnect the heating element and see if your issue goes away.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284081 is a reply to message #284067] |
Wed, 05 August 2015 22:13 |
Dan
Messages: 99
Registered: August 2014
Location: Allentown, NJ
Karma: 0
|
Member |
|
|
Thank you for the help guys! Is there a way to tell if the chassis is getting voltage, without trying to electrocute myself? I want to eliminate bad wiring at the campsite. We had to borrow a long 30A extension at that particular site. Also the electric hot water heater is switched off, (there is a switch in the electrical cabinet) I assume this elements the heater as a point of failure.
Dan
Dan DeLuca
1978 Eleganza II (http://imgur.com/gallery/YFHhK)
Parked at Evil Monkey Farm in
Allentown, New Jersey
|
|
|
|
| Re: [GMCnet] Chassis Voltage When hooked up to shore power [message #284084 is a reply to message #284081] |
Wed, 05 August 2015 22:35 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
|
Senior Member |
|
|
NO, turning the switch off does NOT eliminate the water heater element as a
possible source of leakage.
The campsite wiring COULD be faulty, but you should not be satisfied even
if it was. The leakage voltage you sensed should have been dissipated by
the ground lead in the cable. But more importantly, that leakage should
never have occurred! You DO have a problem somewhere in the coach. Since
we're very sensitive to such leakage, it may be a very small problem, but
it IS a problem, and could become worse at any moment.
The procedures you need to follow are all covered in detail in Ken B's
tutorial; download it now.
Ken H.
On Wed, Aug 5, 2015 at 11:13 PM, Daniel DeLuca wrote:
> Thank you for the help guys! Is there a way to tell if the chassis is
> getting voltage, without trying to electrocute myself? I want to eliminate
> bad
> wiring at the campsite. We had to borrow a long 30A extension at that
> particular site. Also the electric hot water heater is switched off,
> (there is
> a switch in the electrical cabinet) I assume this elements the heater as a
> point of failure.
>
>
> Dan
> --
> Dan DeLuca
> 1978 Eleganza II
> Parked at Evil Monkey Farm in
> Allentown, New Jersey
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
|
|
|
|
| Re: [GMCnet] Chassis Voltage When hooked up to shore power [message #284092 is a reply to message #284084] |
Thu, 06 August 2015 00:34 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
I do not always word things clearly. Let me try it this way. You have a minimum of 2 problems.
The first is that your green wire / safety ground is not attached between a good earth ground suppled by the park service on one end and the chassis of the coach on the other end. If it was attached correctly you would not be getting shocked. I can not tell you where the open or where erroneous connection is. It could be inside your coach or in any adapter or extension cord you are using. It also could be in the actual service provided by the park where you are camping.
The second problem you have is something is putting voltage on the chassis of your coach. I gave you one possibility which is the heater element. If the "green wire" ground circuit in the previous paragraph was working correctly then the voltage you are experiencing would be bled off by the ground circuit and you would not be getting shocked. You must disconnect both wires to the heater element to eliminate it. Simply turning off the switch will not do it.
So open the circuit breaker panel with the power cord disconnected and verify that the heavy cable going to shore power has the green wire connected to the frame of the circuit breaker box. Also look for a wire from that same terminal strip going to the body of the coach. I have forgotten exactly what size that wire is and where it runs to.
If you have an ohm meter with you, you can meter from the ground terminal of the shore power plug to the chassis of the coach. It should read ZERO ohms or one or two 1/10ths of an ohm. If all of that is correct, then start looking at any adapters or extension cables you are using.
I do not know if you are connected to 120 or 240 volts at the park. If it is 120 volts, then you could plug your 3 light service checker direct onto the park supply. If you do not have one then buy one from Lowes, Home Depot, Menards, or your favorite hardware store. They are less than $10.00. Carry it in your coach and check the power at any place that you intend to plug the coach in to in the future.
http://www.amazon.com/gp/product/B000RUL2UU/ref=pd_lpo_sbs_dp_ss_1?pf_rd_p=1944687682&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B001M0M E7E&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=11QBGFKB72RSDF4YH5AQ
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
[Updated on: Thu, 06 August 2015 00:35] Report message to a moderator |
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284097 is a reply to message #284067] |
Thu, 06 August 2015 02:41 |
appie
Messages: 902
Registered: April 2013
Location: denmark
Karma: 2
|
Senior Member |
|
|
Yes a problem with the ground
But I do not think there nessecarely is a problem with couch. Ground can have different vallues and there can be a voltage difference between a perfectly sound couch and a given ground. Enough to be felt, but in the milliA range. A good ground connection will equilize the difference
But meassure the voltage and Amps between couch and ground to be sure there is nothing dangeres
Appie
eleganza 76 "Olga" now sadly sold
6 wheel discbrake
Quadrabags
Springfield stage 2 462 olds
Manny tranny
( pictures at http://www.gmcmhphotos.com/photos/g6489-olga.html
Fulltiming in Europe july 2014 til july 2016
Denmark
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284099 is a reply to message #284097] |
Thu, 06 August 2015 06:27 |
tphipps
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
|
Senior Member |
|
|
Highly recommend the 3 light Service checker. I hae it plugged in all the time in the bathroom. It also makes a great night light.
Last park that I stayed in had reversed neutral and hot leads.
Tom, MS II
2012 Phoenix Cruiser model 2552
KA4CSG
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284109 is a reply to message #284067] |
Thu, 06 August 2015 08:33 |
Dan
Messages: 99
Registered: August 2014
Location: Allentown, NJ
Karma: 0
|
Member |
|
|
I am going to pick up a three light tester. I have checked the connection from the green wire to the chassis and it is clean and solid. Putting between 0 and 2/10th on the ohm meter. I will double check any adapters I use. As for the voltage leakage, most common is the water heater, but is there anyway to tell short of disconnecting the water heater? I installed a new water heater this spring btw, really really don't want to take that apart again.
Dan DeLuca
1978 Eleganza II (http://imgur.com/gallery/YFHhK)
Parked at Evil Monkey Farm in
Allentown, New Jersey
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284111 is a reply to message #284067] |
Thu, 06 August 2015 08:48 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
|
Senior Member |
|
|
Has this happened everywhere or only at one particular hook up? Also look for "bumps" in your power cord where thw internals have failed from repeated bad coiling practices and age. I won't go into all the details as you have the link to folliow where Ken B has spelled it all out.
John Lebetski
Woodstock, IL
77 Eleganza II
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284112 is a reply to message #284067] |
Thu, 06 August 2015 08:54 |
Dan
Messages: 99
Registered: August 2014
Location: Allentown, NJ
Karma: 0
|
Member |
|
|
I have only noticed it once. Then again I generally don't have to crawl around under the coach when camping. (so far) I have read the article, and I am still not sure how to check the hot water heater for leakage. I guess I need to open it up as it is hard wired. I will defiantly check the microwave as I installed that recently and the receptacle did not look great.
Dan DeLuca
1978 Eleganza II (http://imgur.com/gallery/YFHhK)
Parked at Evil Monkey Farm in
Allentown, New Jersey
|
|
|
|
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284170 is a reply to message #284167] |
Thu, 06 August 2015 21:55 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
Please do not get carried away chasing the heater. Fix the Green Wire Ground problem first. I'll bet that you will find the problem is in the extension cable, or adapter, or with the park power supply. Get a 3 light tester and use it.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284179 is a reply to message #284170] |
Fri, 07 August 2015 03:02 |
cadelec
Messages: 303
Registered: September 2011
Location: Brisbane Australia
Karma: 1
|
Senior Member |
|
|
I am in Australia and all outlets in parks are required to have RCD protection i think you call them Ground Fault Interupters Is this not mandatory in the USofA
also when you are running the onan is there then a connection between neutral and earth so any onboard GFI's will operate correctly
Trevor
Brisbane Australia
Siesta Koala 76 Edgemont (old Bobby Moores)
71 Cadillac Eldo Convert
58 Cadillac Eldorado Brougham Project
|
|
|
|
|
|
| Re: [GMCnet] Chassis Voltage When hooked up to shore power [message #284237 is a reply to message #284236] |
Fri, 07 August 2015 18:48 |
tphipps
Messages: 3005
Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
|
Senior Member |
|
|
The plug is readily available at both Camping World and most Wal-Marts for those who cannot wait. I especially like the pull handle. No need to futz with the plug and aligning the prongs. I installed on on my friends Casita, liked it so much, I installed it on my Avion.
Tom, MS II
2012 Phoenix Cruiser model 2552
KA4CSG
|
|
|
|
| Re: Chassis Voltage When hooked up to shore power [message #284259 is a reply to message #284067] |
Sat, 08 August 2015 01:56 |
appie
Messages: 902
Registered: April 2013
Location: denmark
Karma: 2
|
Senior Member |
|
|
Even when RCD protection is mandetory, that does not mean that they are in working order!
To be safe one should have one installed in the couch as well. Ypu could still feel a tinkling, but it would not be unsafe
Appie
eleganza 76 "Olga" now sadly sold
6 wheel discbrake
Quadrabags
Springfield stage 2 462 olds
Manny tranny
( pictures at http://www.gmcmhphotos.com/photos/g6489-olga.html
Fulltiming in Europe july 2014 til july 2016
Denmark
|
|
|
|
|
|
GMCforum
Search
Help
Register
Login
Home
