Transfer Switch or?

[NWILSON]

We are staying at an informal campground with only 20A electric available. We've been in the same site the last 4 yrs and pretty familiar with what we can and can't do electric-wise.
I turned on the microwave at lunch and immediately lost all AC power which I attributed to the surge protector doing it's job. (As I said, this is an informal campground and sometimes voltage gets pretty low due to high power consumption by the residents) The issue was quickly resolved by firing up the generator.
When lunch was over the genny was shut down and we left the site for the afternoon's events. Upon return about 4 hrs later we still had no AC power. I took a look at the display on the Surge Protector this time to find it saying "Reverse Polarity- Remove Power". While anything is possible I doubt that anything took place that could have changed the hard wiring in the campground so I'm thinking something has cooked itself in the Transfer Switch.
I tried different cords and adapters, all with the same result.
This morning's project is to empty the basement and find my way to the transfer switch to check for loose wiring or any other obvious issues.
Thoughts anyone?

 

[danemayer]

Hi Neale & Leslie,

First, I'm assuming your EMS is hard-wired in-between the transfer switch and the breaker panel.

Second, in what you've done so far, I'm assuming you flipped the pedestal breaker off and on without clearing the error condition.

I'm hard put to imagine that the shore power side of your transfer switch flipped polarity (unless the contactors fell apart, causing an internal short). It seems much more likely that something happened in the campground, not necessarily right at your pedestal. If voltage was applied to the neutral line by way of a short circuit somewhere, that might have triggered a false reverse polarity reading.

Have you put a voltmeter on the pedestal outlet to verify 120V from hot to ground and 120V hot to neutral, and 0 volts from neutral to ground?

 

[NWILSON]

Hi Dan!
Thanks for the quick reply!
Yes, the Surge Guard is between the transfer switch and the breaker panel and yes, I reset the pedestal breaker with no change in status.
Putting a volt meter on the outlet didn't show anything abnormal.
Considering all that together makes me think that the load of the microwave was the last straw for something in the transfer switch. I'm hoping the old, fat guy can get to it without too many groans and scratches!

 

[jnbhobe]

I would check the pedestal with a meter first or get a $3 tester from harbor freight and plug that in.

 

[avvidclif]

Hi Dan!
Thanks for the quick reply!
Yes, the Surge Guard is between the transfer switch and the breaker panel and yes, I reset the pedestal breaker with no change in status.
Putting a volt meter on the outlet didn't show anything abnormal.
Considering all that together makes me think that the load of the microwave was the last straw for something in the transfer switch. I'm hoping the old, fat guy can get to it without too many groans and scratches!

The transfer switch is a big relay. I don't know of any way it can reverse the polarity. If you have the Progressive EMS and it shows polarity reversed something isn't right at the pedestal. Do you have one of the plug-in testers that shows reverse polarity? That would answer your question.

 

[Capt7383]

My ems threw a reverse polarity after two years in the same Campground. I like a dummy shut off ems ,after all everything worked fine. Next day grandaughter went to shut off hose at the street next to pedestal. She says to me somethings wrong my fingers tingle. I go shut off water no problem. Neighbor who is electrician connects tester from neutral to ground and gets 96 volts at pedestal. I was wearing shoes, grandaughter wasn't. Trust the ems

Sent from my VS986 using Tapatalk

 

[NWILSON]

Problem is resolved.

The plug in tester showed nothing abnormal so I emptied the basement and located the transfer switch (1st picture)....

Sure glad I did as 4 of the screws securing the wires to the relays were loose but, luckily, no signs of damage yet.
After tightening the screws I reconnected service and this time got a "High Voltage" message from the Surge Guard. Back to the pole....(remember, my "pedestal" is a phone pole with a couple 20amp outlets) The volt meter showed 138 volts just like the Surge Guard inside. After checking outlets at another pole to confirm my meter wasn't applying for a one-way trip to the landfill I located the staff electrician and told him my story. His response was "you've lost neutral!" Opening the circuit breaker box above the outlets revealed a charred white wire confirming his diagnoses. Once corrected the Surge Guard was happy and we were again living with the use of all of our modern appliances.

The people camping next to us did not have any kind of EMS. They only noticed an occasional light dimming. Luckily they moved their connection to a different pole before the voltage readings started showing so high.

We had a single issue that was causing more than one issue with our service. Capt7383 is exactly right...TRUST YOUR EMS. It probably saved us from an unscheduled replacement of all the 110v items in the rig.

While I had the basement emptied I also opened the panel to expose our Progressive Dynamics Converter (second picture).
Thanks to all for their comments and input!