Bad ground?

Right, should be zero to low millivolts depending on the load current in the neutral wire.

IMO, the bad pedestals probably had a bad ground, as in open and/or resistive path back to the point of supply bonding between the neutral and ground.

Second thought, could have been a high resistive neutral wire as well. If you were to take a VAC reading from the Ground to Earth at the pedestal we might then know which...........

Thanks. Wasn't sure about that.

But can't do your test as we're moving on. Told the Campground about it but he was only a Summer student, so who knows if it'll ever be fixed. Brand new installation too.

QUOTE:
"There should be solid 0V between neutral and ground at the pedestal, right?"
END QUOTE


Right, should be zero to low millivolts depending on the load current in the neutral wire.

IMO, the bad pedestals probably had a bad ground, as in open and/or resistive path back to the point of supply bonding between the neutral and ground.

Second thought, could have been a high resistive neutral wire as well. If you were to take a VAC reading from the Ground to Earth at the pedestal we might then know which...........

Just ran into an "Open Ground" error using my Prog. Dyn. EMS
These were relatively new pedestals with only 15-20A receptacles.

Spent some time with a VOM trying to find a good pedestal but it seemed that most had ~10V between Neutral and ground. Others seemed to drift around a lot.

There should be solid 0V between neutral and ground at the pedestal, right?

Anyway, finally went to an older section of the park with 30A sockets, and the EMS is happy. Even when I use our 15A adapter, so I know it wasn't our adapter's problem.

This is the second time our EMS has alerted us to electrical problems on this trip to Eastern/Maritime Canada. Never had any problems before. Visitors beware.

Ok, so I got Back home and found another one of those three light testers and it all tested ok. I tried the original one in the s+b house it it showed the same bad ground issue. So I got that cleared up.
Bad tester or whatever..thanks all

Thanks guys for all the responses I'm not in a position right now to run any tests but as soon as I can I'll follow your advice thanks

First, test the tester to make sure it works correctly. Then, starting at the power source, test at every junction. Test the house outlet/pedestal outlet. Test at the adapter, if using one. Test at the extension cord if using one. Test at the breaker box, and so on. When you find the first location with no ground connection, you have narrowed down the possibilities immensely.

I had to do that when my RV was new. After about a year, I installed a Progressive Industries EMS-HW30C, and it would NOT allow power in. It said open ground connection. For a year, I had not known there was no ground connection. I started at the pedestal and tested at every junction. I found that the ground wire had pulled out of the wire nut where the shore cord was tied in to the RV wiring.

MrWizard wrote:
myredracer

i think you got that mixed up

open ground , tester does not sense/find neutral potential on ground

open 'NEutral' could mean neutral power thru ground circuit and HOT skin on RV

You are right, thanks. I had open ground on my brain.

Never mind

Ok, Electrical 1.01

The way those testers work is they look to see where there is , and where therre is not. voltage.. You should have 120 volts from HOT to Neutral, and from HOT to Ground.. and zero from neutral to ground

In an RV the ground is indeed floating, and if you are using a generator to power the RV odds are very good it is not grounded.. THUS you can get some real strange readings on those 3 light testers.

Now, when on SHORE power, you have one pin on the plug that is kind of round, (may be U or D shaped but kind of round) and the other pins are FLAT.

That different pin.. that is the ground

It is SUPPOSED to be connected to the neutral at the service entrance (That is the main park distribution panel) but in many parks.. it might not be.

And of course there is always the posibility of a broken wire, or bad connection within your RV...

Suggestion>> Find out which.

myredracer

i think you got that mixed up

open ground , tester does not sense/find neutral potential on ground

open 'NEutral' could mean neutral power thru ground circuit and HOT skin on RV