Tips on Finding Hot Skin Source - R-pod Owners Forum

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StephenH

podders Helping podders - pHp

Joined: 29 Nov 2015
Location: Wake Forest, NC
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Posts: 6288

Topic: Tips on Finding Hot Skin Source
Posted: 12 Jul 2020 at 7:41am

Please call is shock. Electrocution is a fatal dose of electricity (electrical execution is where it comes from). What happens to most people is being shocked, but the risk of a fatal shock under certain circumstances does exist.

When I was at Fort Hood, we had one truck and shelter in particular that was bad. At night, I could see the electricity sparking between the ladder and the ground. This is even with things being grounded with a long copper grounding rod.

StephenH
Happy is the man that findeth wisdom,...

ouR escaPOD mods
Former RPod 179
Current Cherokee Grey Wolf 24 JS

Grant177

Groupie

Joined: 15 Mar 2020
Location: Edmonton, AB
Online Status: Offline
Posts: 65

Posted: 11 Jul 2020 at 10:06pm

Hey @offgrid,

Just did another round of testing today (as I was at the trailer and replacing the AC electrical switch for the hot water heater which had fried during previous events).

I've still been unable to replicate any electrical fault since the original electrocution event and after replacing the heating element, thermostat, and switch.

Tested resistance from numerous AC electrical ground locations (ground plug on various AC plugs, inside and exterior, ground bar in fuse box, and copper ground wire coming from fuse panel.

In all locations, resistance from chassis to ground location was always under 1 ohm. So, all I can really say is that other than blaming the camp ground voltage supply for an improper ground, my FIRST thing I'll be testing EVERY time I plug in the trailer is electricity on the chassis...

Picked up one of these to stay with the trailer at all times....

https://www.homedepot.ca/product/klein-tools-non-contact-voltage-tester/1000664603

Not sure if it is just me, but also seems to be a LOT of electrocution threads here lately?

Grant
2011 R-Pod 177

offgrid

Senior Member

Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290

Posted: 02 Jul 2020 at 3:47pm

The element was probably run without water in the tank at some point. It then overheated and created a resistive fault to the tank (and therefore to ground. Resistive because if it was a dead short it would have tripped a breaker in the trailer panel. But the current flowing into the fault was sufficient to eventually cause the poppet thermostats and the switch to overheat. That is interesting and a bit concerning because those items should be able to handle the current flow. I'm becoming suspicious of the water heater breaker in your trailer panel.

I would also still confirm that you have a good ground connection between the chassis and the ground pin in your power inlet. That is very important to assure safety. You don't want to be working on this stuff with the chassis hot.

1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold

Grant177

Groupie

Joined: 15 Mar 2020
Location: Edmonton, AB
Online Status: Offline
Posts: 65

Posted: 02 Jul 2020 at 3:23pm

So, this was the next piece of the puzzle (after replacing the heating element and still not heating).

....so, after replacing that with a new one, plugging in the trailer, I was getting heat...YEAHHH! And still no detectable trace of any power going to the chassis.

So, after getting it all back put together, I go to turn it OFF, and guess what...the AC power switch in the water heater compartment also appears to have fused now....cannot turn it off...sheesh...what next.

So, turned it off at the breaker and have to replace that next...

Whatever cooked the element appears to have done a job on the entire water heater electrical system.

Grant
2011 R-Pod 177

Grant177

Groupie

Joined: 15 Mar 2020
Location: Edmonton, AB
Online Status: Offline
Posts: 65

Posted: 29 Jun 2020 at 10:50am

Yes, I believe that was one of the things I tested and there was electrical connection from chassis ground to AC electrical ground. I'll double check that when I go out again just to make sure.

Grant
2011 R-Pod 177

mcarter

podders Helping podders - pHp

Joined: 07 Apr 2016
Location: Greenbrier, TN
Online Status: Offline
Posts: 3419

Posted: 29 Jun 2020 at 8:50am

Mike Carter
2015 178
" I had the right to remain silent, I just didn't have the ability."

offgrid

Senior Member

Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290

Posted: 29 Jun 2020 at 5:25am

Did you check the resistance between your power inlet ground pin and the chassis? You might still be missing a connection from the chassis to the panel equipment ground buss. If that was intact you shouldn't have developed the voltage from chassis to earth that you did, unless of course that campground's electrical distribution system was faulty.

1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold

Grant177

Groupie

Joined: 15 Mar 2020
Location: Edmonton, AB
Online Status: Offline
Posts: 65

Posted: 28 Jun 2020 at 9:16pm

So, after a pretty full day of troubleshooting.....and playing follow the wire, ran into a couple issues.

Could not under any situation detect any hot skin voltage. Nothing. Took every test I could think of. So, was thinking it was maybe the campground power...

Then tried out with the heating element test. Nothing. Could not detect anything so removed it (see picture) and replaced it. Was hoping all would be done after this...

...but as it is with my life...no such luck. Drove me crazy after that point...was getting no power at the element terminal, but there was 120v at the switch.

Taking voltages at so many points I finally figured out behind the black rubber "reset" pad there are two sets of thermostats/high limit switches (or some other protection device).

They look look like this....the propane side is fine...but the AC side is fried. The "wire" shown between the two terminals is cooked in half.

So...another part to order...but at least tracked it down....I think.

So, the "hot skin" problem still not 100% solved, but I can't seem to re-create it...so likely a combination of the water heater element and/or campground power...or both.

Will update when fixed once and for all...

Grant
2011 R-Pod 177

offgrid

Senior Member

Joined: 23 Jul 2018
Online Status: Offline
Posts: 5290

Posted: 27 Jun 2020 at 5:27am

Well this is getting interesting.

The national electric code requires there to be a bonding conductor connecting the chassis of an RV to the equipment grounding buss in the RV panel board. For the record, this is Article 551.56 (B) in the 2020 Code. If that is connected them you shouldn't have much voltage between earth and the chassis (but it can be more than mcarter's 2/3 volt especially in a RV park where the earth ground at the park service panel might be pretty far away).

I'm practically never plugged into mains power so I've never verified that on my trailer. Well, guess what, I show an open on my ohmmeter between the ground pin on my power inlet and the chassis. If you have this condition it is very easy to develop a high voltage between the chassis and earth ground, in fact typically you will have some voltage roughly midway between 0 and 120V depending on the actual resistance between the chassis and earth vs the chassis and the line voltage in your 120V circuits.

So, I would check that first. Pull the cord and measure the resistance between each of the 3 pins and the frame of the trailer. The ground pin should be low resistance, the other two pins should show open. There should NOT be a connection at the trailer (or a the pedestal) between the neutral and equipment ground conductors. Those should only be connected at the park (or your home) service panel.

My ground pin is open so now I've got to go back and find out why, presumably a terminal somewhere has corrosion on it....could be that's your problem too.

1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold

mcarter

podders Helping podders - pHp

Joined: 07 Apr 2016
Location: Greenbrier, TN
Online Status: Offline
Posts: 3419

Posted: 26 Jun 2020 at 6:49pm

That is a good plan. We all started somewhere. Half the fun. You get it back on a reliable power source and don't see issue, that would be good. I check mine here at house on occasion. I know the trailer is good. I always check when I go to a campsite, so far so good. I was talking to a guy on another forum, who is in a campground established in 1938. I'd check. Just a point, the potential can exist in a dry condition, it becomes dangerous when the ground is wet and a person makes contact to trailer and the ground.

Mike Carter
2015 178
" I had the right to remain silent, I just didn't have the ability."

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StephenH Members Profile Send Private Message Find Members Posts Add to Buddy List podders Helping podders - pHp Joined: 29 Nov 2015 Location: Wake Forest, NC Online Status: Offline Posts: 6288	Topic: Tips on Finding Hot Skin Source Posted: 12 Jul 2020 at 7:41am
	Please call is shock. Electrocution is a fatal dose of electricity (electrical execution is where it comes from). What happens to most people is being shocked, but the risk of a fatal shock under certain circumstances does exist. When I was at Fort Hood, we had one truck and shelter in particular that was bad. At night, I could see the electricity sparking between the ladder and the ground. This is even with things being grounded with a long copper grounding rod.
	StephenH Happy is the man that findeth wisdom,... ouR escaPOD mods Former RPod 179 Current Cherokee Grey Wolf 24 JS

Grant177 Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: 15 Mar 2020 Location: Edmonton, AB Online Status: Offline Posts: 65	Posted: 11 Jul 2020 at 10:06pm
	Hey @offgrid, Just did another round of testing today (as I was at the trailer and replacing the AC electrical switch for the hot water heater which had fried during previous events). I've still been unable to replicate any electrical fault since the original electrocution event and after replacing the heating element, thermostat, and switch. Tested resistance from numerous AC electrical ground locations (ground plug on various AC plugs, inside and exterior, ground bar in fuse box, and copper ground wire coming from fuse panel. In all locations, resistance from chassis to ground location was always under 1 ohm. So, all I can really say is that other than blaming the camp ground voltage supply for an improper ground, my FIRST thing I'll be testing EVERY time I plug in the trailer is electricity on the chassis... Picked up one of these to stay with the trailer at all times.... https://www.homedepot.ca/product/klein-tools-non-contact-voltage-tester/1000664603 Not sure if it is just me, but also seems to be a LOT of electrocution threads here lately?
	Grant 2011 R-Pod 177

offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Posted: 02 Jul 2020 at 3:47pm
	The element was probably run without water in the tank at some point. It then overheated and created a resistive fault to the tank (and therefore to ground. Resistive because if it was a dead short it would have tripped a breaker in the trailer panel. But the current flowing into the fault was sufficient to eventually cause the poppet thermostats and the switch to overheat. That is interesting and a bit concerning because those items should be able to handle the current flow. I'm becoming suspicious of the water heater breaker in your trailer panel. I would also still confirm that you have a good ground connection between the chassis and the ground pin in your power inlet. That is very important to assure safety. You don't want to be working on this stuff with the chassis hot.
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

Grant177 Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: 15 Mar 2020 Location: Edmonton, AB Online Status: Offline Posts: 65	Posted: 02 Jul 2020 at 3:23pm
	So, this was the next piece of the puzzle (after replacing the heating element and still not heating). ....so, after replacing that with a new one, plugging in the trailer, I was getting heat...YEAHHH! And still no detectable trace of any power going to the chassis. So, after getting it all back put together, I go to turn it OFF, and guess what...the AC power switch in the water heater compartment also appears to have fused now....cannot turn it off...sheesh...what next. So, turned it off at the breaker and have to replace that next... Whatever cooked the element appears to have done a job on the entire water heater electrical system.
	Grant 2011 R-Pod 177

Grant177 Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: 15 Mar 2020 Location: Edmonton, AB Online Status: Offline Posts: 65	Posted: 29 Jun 2020 at 10:50am
	Yes, I believe that was one of the things I tested and there was electrical connection from chassis ground to AC electrical ground. I'll double check that when I go out again just to make sure.
	Grant 2011 R-Pod 177

mcarter Members Profile Send Private Message Find Members Posts Add to Buddy List podders Helping podders - pHp Joined: 07 Apr 2016 Location: Greenbrier, TN Online Status: Offline Posts: 3419	Posted: 29 Jun 2020 at 8:50am
	+1
	Mike Carter 2015 178 " I had the right to remain silent, I just didn't have the ability."

offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Posted: 29 Jun 2020 at 5:25am
	Did you check the resistance between your power inlet ground pin and the chassis? You might still be missing a connection from the chassis to the panel equipment ground buss. If that was intact you shouldn't have developed the voltage from chassis to earth that you did, unless of course that campground's electrical distribution system was faulty.
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

Grant177 Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: 15 Mar 2020 Location: Edmonton, AB Online Status: Offline Posts: 65	Posted: 28 Jun 2020 at 9:16pm
	So, after a pretty full day of troubleshooting.....and playing follow the wire, ran into a couple issues. Could not under any situation detect any hot skin voltage. Nothing. Took every test I could think of. So, was thinking it was maybe the campground power... Then tried out with the heating element test. Nothing. Could not detect anything so removed it (see picture) and replaced it. Was hoping all would be done after this... ...but as it is with my life...no such luck. Drove me crazy after that point...was getting no power at the element terminal, but there was 120v at the switch. Taking voltages at so many points I finally figured out behind the black rubber "reset" pad there are two sets of thermostats/high limit switches (or some other protection device). They look look like this....the propane side is fine...but the AC side is fried. The "wire" shown between the two terminals is cooked in half. So...another part to order...but at least tracked it down....I think. So, the "hot skin" problem still not 100% solved, but I can't seem to re-create it...so likely a combination of the water heater element and/or campground power...or both. Will update when fixed once and for all...
	Grant 2011 R-Pod 177

offgrid Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 23 Jul 2018 Online Status: Offline Posts: 5290	Posted: 27 Jun 2020 at 5:27am
	Well this is getting interesting. The national electric code requires there to be a bonding conductor connecting the chassis of an RV to the equipment grounding buss in the RV panel board. For the record, this is Article 551.56 (B) in the 2020 Code. If that is connected them you shouldn't have much voltage between earth and the chassis (but it can be more than mcarter's 2/3 volt especially in a RV park where the earth ground at the park service panel might be pretty far away). I'm practically never plugged into mains power so I've never verified that on my trailer. Well, guess what, I show an open on my ohmmeter between the ground pin on my power inlet and the chassis. If you have this condition it is very easy to develop a high voltage between the chassis and earth ground, in fact typically you will have some voltage roughly midway between 0 and 120V depending on the actual resistance between the chassis and earth vs the chassis and the line voltage in your 120V circuits. So, I would check that first. Pull the cord and measure the resistance between each of the 3 pins and the frame of the trailer. The ground pin should be low resistance, the other two pins should show open. There should NOT be a connection at the trailer (or a the pedestal) between the neutral and equipment ground conductors. Those should only be connected at the park (or your home) service panel. My ground pin is open so now I've got to go back and find out why, presumably a terminal somewhere has corrosion on it....could be that's your problem too.
	1994 Chinook Concourse 1995 RV6A Experimental Aircraft 2015 Rpod 179 - sold

mcarter Members Profile Send Private Message Find Members Posts Add to Buddy List podders Helping podders - pHp Joined: 07 Apr 2016 Location: Greenbrier, TN Online Status: Offline Posts: 3419	Posted: 26 Jun 2020 at 6:49pm
	That is a good plan. We all started somewhere. Half the fun. You get it back on a reliable power source and don't see issue, that would be good. I check mine here at house on occasion. I know the trailer is good. I always check when I go to a campsite, so far so good. I was talking to a guy on another forum, who is in a campground established in 1938. I'd check. Just a point, the potential can exist in a dry condition, it becomes dangerous when the ground is wet and a person makes contact to trailer and the ground.
	Mike Carter 2015 178 " I had the right to remain silent, I just didn't have the ability."