Electrical Question???

stearn · 04-09-2010, 06:30 PM

Today I noticed my heat pump started switching on and off. It also doesn't seem to cool down the coach, however cold air seems to be coming from the vents. I also noticed that the meter shows I'm on 30 amp. I am plugged into a 50 amp. I called the office to report the problem and since the park is pretty empty, I was able to move to a different area. Things seemed a little better meaning the gauge still only showed me on 30 amp but with the fridge on ac and heat pump on I was only showing 8 amps being used, where before it read 26 amps. The electric heater has also quite working. I have checked circuit breakers and all seem to be ok. I did clean the prongs on the plug just in case, but they didn't look bad. I am at a loss hoping for some ideas. We are heading north Sunday, but will be on line when stopped. Thanks

Flagelpater · 04-09-2010, 06:58 PM

IMO You need to take some readings at the campground pedestal with a voltmeter. The 8 amp indication does not sound appropriate to me. I am not an expert but I know when one checks in here he will need a lot more INFO from you. Also, check all of your breakers. Does the unit work okay with the GenSet? When did it last work okay?

TBI · 04-09-2010, 07:21 PM

I agree with Flagelpater, you need a meter. If you show only 30 amps available you are missing one leg of you service. It could be at the campground pedistal. You should measure 240 VAC between the two legs or 120 VAC from each to ground. If you have it there, check inside your panel in your motorhome. If you have it both places its probably the power management system and I can't help there.

stearn · 04-10-2010, 10:04 AM

With the generator running all seems to be fine. I had the pole checked and both sides read 119. We also checked the outlets in the coach and they were all showing around the 120. On my power board it only shows me being plugged into 30amp, and with the hot water electric heater on and a table fan. and tv, plus the refidge the amp gauge on the power board only registers 5 amps being used. The water is probably warm enough that it is not on as I would supect it to pull more than 5 amps when warming the water. Is it possible the converter went bad??

RustyJC · 04-10-2010, 10:22 AM

Quote:

Originally Posted by stearn

I had the pole checked and both sides read 119.

Did L1 to L2 read 240VAC (correct) or 0VAC (wrong)?

Rusty

dirko · 04-10-2010, 10:26 AM

Hi Ho:

Quote:

Originally Posted by stearn

With the generator running all seems to be fine.

Does this mean that the electric heater works? Does it mean that you show 50 amps?

The problem with analyzing your situation is that things just aren't consistent. For example, the heat pump (I assume on cooling) doesn't
cool the coach, but there is cold air coming out of the vents?

I would be glad to try to help, but don't understand the situation. I do have a master's degree in electrical engineering and understand how motorhomes are wired, but (except for the 30 amp reading) don't understand what symptoms you are describing.

Dirk

steelheadbluesman · 04-10-2010, 10:32 AM

IMO, your sending unit on the EMS board is most likely the problem. If your wall unit is reporting erroneously, and other indications are good, your EMS board has burnt the sending unit. Couple hundred bucks for a new CB.

I hope you will keep us posted on this, as I've had this problem before and want to learn more about it.... Best of luck to you.

Martind4 · 04-10-2010, 10:45 AM

One more thing to check. Our power transfer switch failed this year with almost the same symptoms you describe. One of the 120v legs coming out of the transfer switch was burned and shorted out. Our pedestal still had 120 v on each leg so we had 50 amps incoming, but the EMS display showed we only had 30 amp because it didn't make it through the transfer switch. Once I removed the cover on the transfer switch, it was real easy to diagnose the problem, the burned wire was very obvious. Replaced the transfer switch and all is well now.

stearn · 04-10-2010, 10:47 AM

I still have hot water while using the electric. The on off switch used to have a light when on but now no light. The a/c (heat pump) cycles on ond off. Which is more often than before, and does not seem to cool the coach down. The panel has an lcd read out that shows 5 amps being used. Thanks for helping

steelheadbluesman · 04-10-2010, 11:26 AM

Quote:

Originally Posted by Martind4

One more thing to check. Our power transfer switch failed this year with almost the same symptoms you describe. One of the 120v legs coming out of the transfer switch was burned and shorted out. Our pedestal still had 120 v on each leg so we had 50 amps incoming, but the EMS display showed we only had 30 amp because it didn't make it through the transfer switch. Once I removed the cover on the transfer switch, it was real easy to diagnose the problem, the burned wire was very obvious. Replaced the transfer switch and all is well now.

Did all your appliances and systems work when one leg was shorted out? It seems that your larger draws would have been shed, like water heater and heat pump.... Just wondering

philbailey · 04-10-2010, 11:40 AM

Judging from other posts and replies I dont think you understood what some were telling about the 50 amp service. I had an electrician install a 50 amp service post at my house for my old coach. I thought it was working fine for the past 5 years. I bought a 2010 Itasca Ellipse in January and brought it home. WHen I plugged it into my "50 amp" service the meter in the coach only showed 30 amp service. After seaching the internet I called a different electrician and had him fix my problem. I wish I could find the info again from my internet search. Here's the problem I (and more than a few campgrounds) had.

Electricity come into our homes in two phases on four wires. L1, L2, neutral and ground. L1 (leg 1) and L2 (leg 2) each have 120V betweeen that leg and neutral. This gives us the ability to have 240V appliances like stoves, driers, etc, by using both L1 and L2. Circuits in the house only use one leg and thus only have 120V. Both legs are used in the house. At the house circuit breaker panel (typically) every other circuit breaker is on the same leg. So CB 1, 3, 5 etc is on leg 1 and CB 2, 4, 6 etc is on leg two.

My first electrician had put my two circuit breakers (remember the two CB switches at the campground service post) on the same leg (CB's were at position 1 and 3, they should have been at position 1 and 2. Some camp grounds evidently only use one leg split to both receptacle plugs so you only get 30 amp, 120 V service even if the CB says 50 amp and the receptacle is a 4 prong 50 amp plug.

You need a meter to check the campground receptacle. You have to have 120 V between L1 and neutral, 120 V between L2 and neutral, and 240V between L1 and L2. Usually the L1 and L2 are the prongs side by side, neutral is the top prong, and ground is the bottom prong. Without the 240V between L1 and L2 some things on some coaches wont work, like my 240V basement air conditioner and you dont have true 50 amp sevice.

Hope this helps.

stearn · 04-10-2010, 12:37 PM

Steelheadbluesman, not sure what your asking, but my electric water heater still works. If I turn the air on then that seems to put a drag on the system. The heat pump will shut on and off . The amp usage showing on the panel will jump as high as 28 amps when it restarts, then settles back to 18 after the inital start surge. I am heading north tomorrow, and will see what happens when I use a different 50 amp service,at another park.
The fellow with the meter only checked two legs each showed 119. He did not connect the two to see if he got the 240.
Where would I find the transfer switch? Is it where the wire goes in the box on the coach?

Martind4 · 04-10-2010, 01:15 PM

On our coach the transfer switch is a black box where the power cord terminates. It switches power between shore power and the generator allowing only once source to be active at a time.

I believe our basement air/heat pump must have both legs (L1 & L2) supplying power to operate both compressors. If one leg is missing only one compressor will work and the entire system will cycle more frequently. If your EMS only recognizes 30 amp supply (L1 only), it could be managing the load by shedding the water heater or heat pump compressor periodically to keep the load under 30 amps. You would still have some hot water available and the heat pump would operate but not at the same time.

RJay · 04-10-2010, 01:28 PM

At the power pedestal the same live leg is feeding both power leads or one of the live legs have become disconnected at the transfer switch. Since you said everything is normal off the generator there is no problem beyond the transfer switch. The other test you can make is to check the continuity of your power cable to make sure a power leg hasn't become detached interanlly from the power cord plug. Good Luck.

hamguy · 04-11-2010, 01:21 PM

Quote:

Originally Posted by Martind4

On our coach the transfer switch is a black box where the power cord terminates. It switches power between shore power and the generator allowing only once source to be active at a time.

I believe our basement air/heat pump must have both legs (L1 & L2) supplying power to operate both compressors. If one leg is missing only one compressor will work and the entire system will cycle more frequently. If your EMS only recognizes 30 amp supply (L1 only), it could be managing the load by shedding the water heater or heat pump compressor periodically to keep the load under 30 amps. You would still have some hot water available and the heat pump would operate but not at the same time.

My basement air works quite nicely on 30A utilizing both compressors. Not much left over though. The two take 24-26A.

stearn · 06-11-2010, 06:37 PM

I finally got our Winne in for its electrical problem. They are replacing bad power boards. The boards have been updated , so to install the new ones they also need to change the wiring harness. Now waiting for parts. Very happy we have the extended warranty ! I will update when I pick it up then I will have the total description of parts replaced.

Bob and Vicki · 06-12-2010, 07:54 AM

We have a 2006 Meridian. When we could not get 50 amps in the coach, only 30. It was our EMS board, there is a new updated board available.

Good Luck,