Hot skin!! Please help!

[Steve D]

The leads from the meter are hooked up to the camper fender and a earth ground.

[jondbar628]

OK, you have a differential between the trailer ground and the earth ground. THis indicates a high-resistance between the two. The ONLY real ground you have is the ground wire in your extension cord to shore power. The trailer ground "floats" otherwise. (Unless you drive a good ground rod) Does your PD4045 have an indicator light when power is applied? this COULD be a source of the problem. almost all devices connect to common (ground) to complete the circuit.

To troubleshoot, disconnect shore power. Connect one end of a wire (long enough to reach the far end of the trailer) to the ground prong of the trailer connection, and the other end to a meter lead. Set the meter on x1 or x10 on the Ohms scale. Starting at the device nearest the trailer connection, read the resistance from the common (not the ground, although it should be the same) across the meter. anything less than an ohm is inconsequential. When you get a significant increase in resistance, you've found (at least one of ) your problem(s). If you don't find ANYTHING reading abnormally, the problem is in the shore-power cord ground..............This is my second post - the first was in more detail, but got timed out.

[low277]

It looks like your getting about 22 volts AC between the fender and earth? This is not normal! You defininetly have a problem. I would double check all of your AC grounding and bonding. If everything is grounded/bonded correctly the issue should be somewhat self diagonistic as a over current protection device will blow or trip.

Be safe, be careful and keep looking.

[Dale M.]

I'm beginning to think that this is just how it's supposed to be. I have all 12v circuits disconnected. I have all 120v disconnected. I have the battery disconnected.
The only things that are still hooked up are the 30a main and the 15a breaker that powers the pd4045. The voltage is still there. If I turn off the 15a that powers up the pd4045 the voltage goes away. I'll post pics of my voltage measuring technique.

IF the PD 4050 has it's OUTPUT BREAKERS OFF and unit is on and voltage is there ... The PD 4045 is source of the problem (voltage)...

Dale

[MtnDon]

Where was the PD unit bought? I recall something about there being some counterfeit PD's being sold at some places online. Could this be related? PDinfo

[Steve D]

I bought it from a reputable dealer.

I'm back to trying to solve the problem. I've been running on batteries

Thanks
Steve

[Shadow Catcher]

Our tear came with a grounding problem. I found that out when I heard the battery boiling and a hot frame. I never did find the problem. Since all the lights had ground wires there was nothing that needed to be grounded to the frame My speculation is that when building some one forgot that white is ground and black is hot. (stupid idea)

[low277]

Any luck finding the source of the voltage on the skin?

[GuitarPhotog]

Any luck finding the source of the voltage on the skin?

Given that the thread is a year and a half old, I hope he found it long ago!

<Chas>

[low277]

The OP posted that he was still working on the problem, curious if if found a solution or is still troubleshooting. Would hate to see anyone get hurt.

[low277]

The OP posted that he was still working on the problem, curious if if found a solution or is still troubleshooting. Would hate to see anyone get hurt.

[Steve D]

Sorry to leave everyone in suspense!

No one got hurt or even tickled yet. As I mentioned, the issue is only there if I use an extension cord with a missing ground prong. When we camped this year we ran off the battery and I charged it when we got back home.

Work has gotten in the way of me diving back into this. I figure that my next step will be to buy a new PD4045 and wire it in and see what happens. As mentioned in this thread I am starting to believe that is the problem. I'v tried everything but that as described in this thread.

It may take a while, but I will pass on what the most probable root cause was.

Thanks
Steve

[Steve D]

OK, you have a differential between the trailer ground and the earth ground. THis indicates a high-resistance between the two. The ONLY real ground you have is the ground wire in your extension cord to shore power. The trailer ground "floats" otherwise. (Unless you drive a good ground rod) Does your PD4045 have an indicator light when power is applied? this COULD be a source of the problem. almost all devices connect to common (ground) to complete the circuit.

To troubleshoot, disconnect shore power. Connect one end of a wire (long enough to reach the far end of the trailer) to the ground prong of the trailer connection, and the other end to a meter lead. Set the meter on x1 or x10 on the Ohms scale. Starting at the device nearest the trailer connection, read the resistance from the common (not the ground, although it should be the same) across the meter. anything less than an ohm is inconsequential. When you get a significant increase in resistance, you've found (at least one of ) your problem(s). If you don't find ANYTHING reading abnormally, the problem is in the shore-power cord ground..............This is my second post - the first was in more detail, but got timed out.

Actually This is next ^^^^ I needed to review this thread to jog my memory as to where I left off on this troubleshooting mission!
I do know that the numbers changed when I kept the outside lights from contacting the side skin.

Thanks
Steve

[Trebor English]

The pd4045 is a switching power supply that generates pulses of current with fast turn on edges. It has some small capacitors to filter high frequency emi, electromagnetic interference, from being radiated by the power cord. There's one from each power leg, neutral and hot, to safety ground. This forms a high impedance voltage divider with safety ground half way between hot and neutral. The pd4045 case is wired to the trailer fender.

With an ideal very high impedance meter the voltage from safety to hot and from safety to neutral should be half the supply voltage. With a real meter that actually puts a load on the circuit being measured you will get less than half the supply voltage but both should be the same as the voltage divider capacitors probably have the same capacitance, plus or minus 10 percent.

To fix this have a complete circuit from safety ground at every load all the way back to the point where neutral and safety are bonded in the main distribution box, circuit breaker box. If you use a generator you are the electric utility and should have safety bonded to neutral at the generator distribution panel.