A Hockey Puck 15/30Amp Adapter to Avoid

Dutch_12078 wrote:

Harvard wrote:

Dutch_12078 wrote:
The safety ground lug should never carry any significant current unless there's a fault elsewhere. A "hot skin" condition only occurs if the neutral and ground are bonded in the RV in violation of the NEC or shorted together, AND the power source hot and neutral are reversed. Just the absence of the ground alone should not cause any problems, although it's certainly not advised to leave it that way in case a fault should occur.

Not so, there is stray capacitance between the H, N and G conductors through out the RV. When the G is allowed to float it will attempt to find a stable level 1/2 way between H and N or some where < 55 VAC. But the extent of current behind this voltage is in the order of being < 5 milliAmps otherwise it would trip GFCIs if there was a GFCI supplying the RV.

Also, quite separate from the presence of 120VAC H and a N circuit wiring, if you park an RV under HIGH VOLTAGE distribution wires (ie 6,000 VAC) and the RV IS NOT CONNECTED to Shore Power AND the RV has no conductive connection to EARTH, that RV frame will develop a hot skin. This type of hot skin is due to the RV being an isolated capacitator plate between the high voltage wire and EARTH.

IMHO.

What part of "significant current" didn't you understand?

Sorry, I should have been more explicit.

A "hot skin" condition is generally accepted as being an RV which has a measureable voltage between the conductive surface (or chassis) of the RV to Earth. It is usually detected by a person in contact with Earth and happens to touch the RV conductive surface.

This "hot skin" condition can be the result of a one fault condition, on a 30 Amp RV. The one fault being an open ground where the RV conductive surface is allowed to float. If there are no other paths from RV chassis to Earth this voltage will amount to be as much as 1/2 the applied H to N VAC on a 30 Amp RV. (I have no personal experience with a 50 Amp RV having an Open Ground Conductor to know what the expected chassis to Earth VAC might be)

That's why I only use the dogbone style of adapter.

Dutch_12078 wrote:

Harvard wrote:

Dutch_12078 wrote:
The safety ground lug should never carry any significant current unless there's a fault elsewhere. A "hot skin" condition only occurs if the neutral and ground are bonded in the RV in violation of the NEC or shorted together, AND the power source hot and neutral are reversed. Just the absence of the ground alone should not cause any problems, although it's certainly not advised to leave it that way in case a fault should occur.

Not so, there is stray capacitance between the H, N and G conductors through out the RV. When the G is allowed to float it will attempt to find a stable level 1/2 way between H and N or some where < 55 VAC. But the extent of current behind this voltage is in the order of being < 5 milliAmps otherwise it would trip GFCIs if there was a GFCI supplying the RV.

Also, quite separate from the presence of 120VAC H and a N circuit wiring, if you park an RV under HIGH VOLTAGE distribution wires (ie 6,000 VAC) and the RV IS NOT CONNECTED to Shore Power AND the RV has no conductive connection to EARTH, that RV frame will develop a hot skin. This type of hot skin is due to the RV being an isolated capacitator plate between the high voltage wire and EARTH.

IMHO.

What part of "significant current" didn't you understand?

I thought Harvard's response was to "hot skin", not "significant current". He in fact said <5 milliamps, which I would not interpret as significant in this context.

I agree on the pucks. A lot of them I used you really had to jam it in there because the holes where not the exact size. Use dog bones now.

But, just from use outside in inclement weather and these adapters/plugs laying on the ground most of the time. How many of you have looked at your blades on the plug itself? Are they crudded up and/or black? Lot of times that is what is causing the resistance and melted adapters. Or the bad adapter causing them to turn black. So when you use a better adapter there is still some resistance.

I file mine down back to shiny copper with a file periodically to prevent the whole cycle of it.

I guess pucks are ok if you want to float your batteries
But not for serious use
I prefer dog bones and even keep a spare

Every small round 30A to 15A Adapter I tried to use always got hot on me in a short period of time. Finally threw all of them away into the local dump...



Have never any problems with my long dogbone style adapters.


I have been using two of these long dogbone type adapters laying in my back yard since around 2009 for my 5th wheel and off-road POPUP trailers sitting in my back yard.

Roy Ken

Harvard wrote:

Dutch_12078 wrote:
The safety ground lug should never carry any significant current unless there's a fault elsewhere. A "hot skin" condition only occurs if the neutral and ground are bonded in the RV in violation of the NEC or shorted together, AND the power source hot and neutral are reversed. Just the absence of the ground alone should not cause any problems, although it's certainly not advised to leave it that way in case a fault should occur.

Not so, there is stray capacitance between the H, N and G conductors through out the RV. When the G is allowed to float it will attempt to find a stable level 1/2 way between H and N or some where < 55 VAC. But the extent of current behind this voltage is in the order of being < 5 milliAmps otherwise it would trip GFCIs if there was a GFCI supplying the RV.

Also, quite separate from the presence of 120VAC H and a N circuit wiring, if you park an RV under HIGH VOLTAGE distribution wires (ie 6,000 VAC) and the RV IS NOT CONNECTED to Shore Power AND the RV has no conductive connection to EARTH, that RV frame will develop a hot skin. This type of hot skin is due to the RV being an isolated capacitator plate between the high voltage wire and EARTH.

IMHO.

What part of "significant current" didn't you understand?

It's not necessarily due to capacitance but the voltage gradient that exists between the high voltage line itself and the ground. If you walk under a utility high voltage transmission line at 230KV or higher, you can take a voltmeter and put one probe in the ground and one in the air and get a reading and the higher in the air you hold a probe, the higher the reading gets. There's an off-leash dog park near us under a 500KV line and you can't walk your dog with a metal leash otherwise you will get a nasty tingling and that's just a couple of feet off the ground. I don't think I'd want to park an RV near one of these lines.

Harvard wrote:

Dutch_12078 wrote:
The safety ground lug should never carry any significant current unless there's a fault elsewhere. A "hot skin" condition only occurs if the neutral and ground are bonded in the RV in violation of the NEC or shorted together, AND the power source hot and neutral are reversed. Just the absence of the ground alone should not cause any problems, although it's certainly not advised to leave it that way in case a fault should occur.

Not so, there is stray capacitance between the H, N and G conductors through out the RV. When the G is allowed to float it will attempt to find a stable level 1/2 way between H and N or some where < 55 VAC. But the extent of current behind this voltage is in the order of being < 5 milliAmps otherwise it would trip GFCIs if there was a GFCI supplying the RV.

Also, quite separate from the presence of 120VAC H and a N circuit wiring, if you park an RV under HIGH VOLTAGE distribution wires (ie 6,000 VAC) and the RV IS NOT CONNECTED to Shore Power AND the RV has no conductive connection to EARTH, that RV frame will develop a hot skin. This type of hot skin is due to the RV being an isolated capacitator plate between the high voltage wire and EARTH.

IMHO.

Dutch_12078 wrote:
The safety ground lug should never carry any significant current unless there's a fault elsewhere. A "hot skin" condition only occurs if the neutral and ground are bonded in the RV in violation of the NEC or shorted together, AND the power source hot and neutral are reversed. Just the absence of the ground alone should not cause any problems, although it's certainly not advised to leave it that way in case a fault should occur.

Not so, there is stray capacitance between the H, N and G conductors through out the RV. When the G is allowed to float it will attempt to find a stable level 1/2 way between H and N or some where < 55 VAC. But the extent of current behind this voltage is in the order of being < 5 milliAmps otherwise it would trip GFCIs if there was a GFCI supplying the RV.

Also, quite separate from the presence of 120VAC H and a N circuit wiring, if you park an RV under HIGH VOLTAGE distribution wires (ie 6,000 VAC) and the RV IS NOT CONNECTED to Shore Power AND the RV has no conductive connection to EARTH, that RV frame will develop a hot skin. This type of hot skin is due to the RV being an isolated capacitator plate between the high voltage wire and EARTH.

IMHO.

Yes avoid them all. Get a dog bone with #10 wire.