Microwave and converter fried at campground

[Mike_Schriber]

Just got set up at a campground in Colorado Springs and I have a big problem. Everything seemed to be working correctly electrically initially but when we came back to camp I found the front air conditioner breaker blown, the microwave off and the battery not charging. I reset the AC breaker and the unit seems fine.
I then checked the outlets for the microwave and converter (each on a separate breaker) and they had power. The converter smells fried and is not putting out any power and the microwave appears to be history.

Doing more testing, I used a circuit checker to test the other outlets. One circuit showed that the hot and ground were reversed (the laptop plugged into that circuit also stopped charging). I switched from the 50 amp plug to the 30 amp and the circuit showed good. I'm now figuring that one leg is wired wrong at the pedestal on the 50 amp outlet. However, I switched back to the 50 amp circuit to double check and now the circuit shows normal.

I'm really stumped. I know it's not anything on the motorhome side but I can't explain the shifting readings. I plan to have some words with the campground management in the morning and I'd love to have some idea what's going on with their power before I do.

Any thoughts?

Thanks!

[CA_Traveler]

wolfe10 wrote:

CA Traveler wrote:

Bobbo wrote:
Correct me if I am wrong, but on a 30 amp circuit, you have a HOT and a NEUTRAL. If the NEUTRAL loses connection (which is what happened to fry his stuff) you have NO CONNECTION. You can only have the 0v and 240v (or low voltage/high voltage) difference if you have both HOTs connected with no NEUTRAL.

You can have very high voltage on 30A due to a open neutral. It happened to me and of course the open neutral was in the CG 120/240V distribution. This is I suspect a rare incident but it happened to me.

Fortunately I had installed a PI full power protector and it disconnected the rig power and no harm. The voltage was displayed on the remote and I could not pull the plug fast enough.

Sorry, not correct.

Yes, on 50 amp (two hots) and open neutral can cause very high/very low voltage.

But, an open neutral on a 30 amp (single hot) will just cause NO POWER.

It is correct and the open neutral is in the 120/240 CG distribution or split phase neutral if you like. I agree that if the hot or neutral is open to a 3 wire circuit there will be no voltage.

But what happened to me is the exact same scenario as an open neutral on a 50A pedestal. But I was on 30A and the open neutral was FURTHER UPSTREAM in the CG 120/240V DISTRIBUTION CENTER.

[doxiemom11]

We had a problem once and it was the cord on our rv. One of the wires inside the molded plug had broken. It was the cord original to our unit and was 10 years old. Our EMS is what made us aware there was a problem as it wouldn't let power thru into our rig. When DH figured it out we replaced the 50 amp cord. He checked the old cord further and the wire was broken right where the cord fastens into the molded plug.

[joshuajim]

A little off topic, but strange things can happen. Many years ago I was building a golf course and working in the construction trailer getting mobilization set up. A crew from SDG&E was working on the power pole near the trailer connecting temporary power for the site.

A worker using a hot stick to connect wires dropped a hot wire and it hit the neutral or ground wire on the pole. Fried just about everything in the trailer. Had I not seen the actual flash on the pole and confronted the crew they would have just finished and quietly snuck away.

[Bobbo]

wolfe10 wrote:

CA Traveler wrote:

Bobbo wrote:
Correct me if I am wrong, but on a 30 amp circuit, you have a HOT and a NEUTRAL. If the NEUTRAL loses connection (which is what happened to fry his stuff) you have NO CONNECTION. You can only have the 0v and 240v (or low voltage/high voltage) difference if you have both HOTs connected with no NEUTRAL.

You can have very high voltage on 30A due to a open neutral. It happened to me and of course the open neutral was in the CG 120/240V distribution. This is I suspect a rare incident but it happened to me.

Fortunately I had installed a PI full power protector and it disconnected the rig power and no harm. The voltage was displayed on the remote and I could not pull the plug fast enough.

Sorry, not correct.

Yes, on 50 amp (two hots) and open neutral can cause very high/very low voltage.

But, an open neutral on a 30 amp (single hot) will just cause NO POWER.

Actually, it is correct. I finally figured out how it can happen.

Let's say you and I are parked next to each other. (Distance really doesn't matter though.) My 30 amp rig is on L1. Your 30 amp rig is on L2. We share a NEUTRAL from our sub-panel.

Now, the NEUTRAL is cut at the main breaker panel, but not at our sub-panel. I get 120v on L1 through my RV, going out our shared NEUTRAL, to the sub-panel (where it can not go back to the main panel due to the cut wire), then to your RV. Our shared NEUTRAL carries my 120v from L1 to your RV's NEUTRAL where it meets your 120v on L2. My 120v on the shared NEUTRAL is added to your 120v on L2 to give us both 240v.

You can test this. Get a 4 gang box. Put 2 duplex outlets in it and a switch. Run L1 to one of the duplex outlets and L2 to the other. Run the NEUTRAL to the light switch (so you can simulate a broken wire), then from the switch, to BOTH of the duplex outlets. With the switch turned ON, plug in the gizmo to a 4 wire 240v outlet.

Both duplex outlets will register 120v.

Turn OFF the switch, simulating the broken NEUTRAL at the main breaker box. Now, both duplex outlets will register 240v.

The 4 wire 240v outlet is the main breaker panel, and your gizmo is the sub-panel. Your voltage tester is your RV.

Of course, SOMETHING needs to be plugged in to each of the duplex outlets so current is flowing. Otherwise, the duplex outlets are merely open switches themselves. Be sure that whatever is plugged into the duplex outlets is safe at both 120v and 240v because it will see both voltages during the test.

[Bobbo]

mike-s wrote:

Bobbo wrote:
FWIW, I bought my PI EMS-HW30C almost 10 years ago and have not plugged in a single time since without it

How many times has it refused to provide power because it sensed an issue?

Over the last 10ish years, it has failed to connect one time due to a power pedestal problem.

Where it really shines, though, is that over the same time frame, it has connected fine, then disconnected much later due to low voltage (hot summer days and lots of air conditioners running) probably 6 to 8 times. That low voltage, repeated on occasion, can kill an air conditioner. The air conditioner dying due to repeated low voltages would have cost me much more than the cost of the EMS.

That is why I laugh when I read a post where someone says he doesn't need an EMS because he checks the voltage before plugging in. Before plugging in, it is probably fine. It gets to be a problem in the late afternoon when he is no longer watching the voltage.

[Mike_Schriber]

Garden of The God's Campground.

RSD559 wrote:
Which campground in Colorado Springs was this? It's good to know that they stepped up and took responsibility. We spent a week at the KOA there earlier this year. Speaking of that KOA, really great water park for the grandkids. It opened the day we left. I guess they open it up to outsiders for a fee. It was well populated. Our daughter said that she would bring the kids across town to play there when it's hot.

[MEXICOWANDERER]

A no contact AC voltage detector can be used to avoid this, period. E=MC2 abtracts are near worthless in comparison. I use the detector on every appliance and on the rig's skin. It's absolutely B.S. proof.

[BadgerMcAdams]

MEXICOWANDERER wrote:
That's called

TOUCH THE SKIN OF THE RIG AND NO NEED FOR MORNING COFFEE

Not sure what you mean, You can get electrical power routed through the skin of the trailer? THAT would definitely be a HOT SHOT in the morning.

[wolfe10]

CA Traveler wrote:

Bobbo wrote:
Correct me if I am wrong, but on a 30 amp circuit, you have a HOT and a NEUTRAL. If the NEUTRAL loses connection (which is what happened to fry his stuff) you have NO CONNECTION. You can only have the 0v and 240v (or low voltage/high voltage) difference if you have both HOTs connected with no NEUTRAL.

You can have very high voltage on 30A due to a open neutral. It happened to me and of course the open neutral was in the CG 120/240V distribution. This is I suspect a rare incident but it happened to me.

Fortunately I had installed a PI full power protector and it disconnected the rig power and no harm. The voltage was displayed on the remote and I could not pull the plug fast enough.

Sorry, not correct.

Yes, on 50 amp (two hots) and open neutral can cause very high/very low voltage.

But, an open neutral on a 30 amp (single hot) will just cause NO POWER.

[CA_Traveler]

Bobbo wrote:
Correct me if I am wrong, but on a 30 amp circuit, you have a HOT and a NEUTRAL. If the NEUTRAL loses connection (which is what happened to fry his stuff) you have NO CONNECTION. You can only have the 0v and 240v (or low voltage/high voltage) difference if you have both HOTs connected with no NEUTRAL.

You can have very high voltage on 30A due to a open neutral. It happened to me and of course the open neutral was in the CG 120/240V distribution. This is I suspect a rare incident but it happened to me.

Fortunately I had installed a PI full power protector and it disconnected the rig power and no harm. The voltage was displayed on the remote and I could not pull the plug fast enough.

[SoundGuy]

Bobbo wrote:
FWIW, I bought my PI EMS-HW30C almost 10 years ago and have not plugged in a single time since without it

mike-s wrote:
How many times has it refused to provide power because it sensed an issue?

Bobbo would have to answer for himself but I typically see my EMS cut off power 3 or 4 times each season while camping, a couple of times from May to Oct while parked and plugged in here at the house. Mostly it's excessively low voltage or loss of ground. Wouldn't ever plug in without it.

[RSD559]

Which campground in Colorado Springs was this? It's good to know that they stepped up and took responsibility. We spent a week at the KOA there earlier this year. Speaking of that KOA, really great water park for the grandkids. It opened the day we left. I guess they open it up to outsiders for a fee. It was well populated. Our daughter said that she would bring the kids across town to play there when it's hot.

[mike-s]

Bobbo wrote:
FWIW, I bought my PI EMS-HW30C almost 10 years ago and have not plugged in a single time since without it

How many times has it refused to provide power because it sensed an issue?

[Bobbo]

So, you are 30 amp on L1, he is 30 amp on L2, and you share a NEUTRAL. The NEUTRAL is cut at the breaker box, but is continuous between the two RVs?

I can see that. Thank you. (In this case, my PI EMS will also save the other guy's electronics.)

FWIW, I bought my PI EMS-HW30C almost 10 years ago and have not plugged in a single time since without it (easy since it is hardwired behind the breaker box). I even took it out and transferred it to the new RV when we traded this year.