Electrical Problems

[randyw]

We purchased our 05 MADP 4030 this past year so when it came to winterizing I sought the help from an experienced RVer friend who has owned a similar coach for many years. I've owned a travel trailer and a 5th wheel, but with the extra appliances in the MADP I thought I should get some help the first time around. I took the coach over to the friends home to do the work as he had everything we needed including a recently installed 30amp circuit.

We plugged into the 30amp circuit and proceeded to winterize. Everything was going well until we turned on the washer/dryer combo to run antifreeze through it. Immediately there was a loud bang/pop followed by the smell of burning electrical and the washer/dryer was dead. A little investigation also showed that the microwave wasn't displaying the time and was also dead and the battery charger wasn't operating.

I disconnected the shore power and started the genset, but same results. After resetting the breaker for the washer/dryer we were able to finish winterizing. If I use the inverter the microwave will work, but not on shore power. Refrigerator and dishwasher works, but still no battery charging. I haven't checked the ac/heat pumps, but will tomorrow when I can start the genset.

I'm assuming that the newly installed 30amp circuit is faulty, but didn't dig into this as it isn't my home. Does anyone have any initial thoughts on what might have been damaged to caused the problems listed above and where I should start?

The unfortunate thing is I purchased a Progressive Power/Surge protector and planned on having an electrician friend install it for me, but he hasn't been available to help.

[randyw]

I should add that I tried an inverter reset by holding the on/off button on the inverter for 15 seconds and longer, but it doesn't seem to reset. It merely turns the inverter on and off.

["007"]

I'm afraid the 30 amp has fried your appliances in your coach if you had a Surge Protector it may not have happened.
Check this link for SP and correct wiring for RV's at the house.
After reading further you may have sacrificed your transfer switch and it maybe what saved everything else.
The same link will have info on TS.
You need a SP in your coach at any rate because your can run into these problems in campgrounds during your travels.
Here is information on winterizing.
In my signature below you will find links to many more for your Newmar.
I would warn your friend not to plug in his coach, in that outlet.
Do you have a Owners Guide for your coach???

[Dutch Star Don]

If the microwave is working off of the inverter, it's okay. It sounds like you fried your transfer switch. That's why there is no power from the generator or the shore cord. The inverter also need's 110 voltage to operate.

[randyw]

The confusing thing is that other appliances are working from shore power and the genset. Only the micro and the battery charger (from what I've found so far) are not working on shore power or genset.

[94-Newmar]

Randyw, as mentioned above by the other posters, your friends new 30amp outlet is most likely wired for 220v, not 120v. It's very common to see this as most electricians see the receptacle and assume it's 220v - which of course it's not. I would suggest he, or someone, check that receptacle with a voltmeter to confirm. Nonetheless, as mentioned above, you most likely cooked your 12vdc converter and your microwave. Any 120v appliance that was not switched on will most likely be ok, but the microwave and converter have no on/off switch and are powered anytime AC voltage is present - which is why it cooked them.

[wa8yxm]

You said "Newly installed 30 amp circuit"......

Was it installed by a professional?

Here is why I ask.. Many converters are dual voltage devices, they do not mind 240 volts. But rather a lot of the rest of the RV does, INCLUDING both the washer/dryer and the Microwave.

Many professionals take a look at that TT-30 outlet which is clearly marked 125 volts AC max (but they do not read that marking) and wire it for an air compressor, welder, or dryer which takes 240 volts.

The result..... Well, you kind of described the result.

Check the outlet voltage before you do anything else.

And one final note: There are other causes for what you describe, but this is #1 on my suspect list.

[Jim T.]

After you get your present problems fixed, you may wish to fabricate one of these to check any power pedestal before plugging in your RV.



Also, congratulations on buying the Progressive Industries EMS-HW50C. Good decision.




FMCA Local Chapter Secretary - Bay Area TravelerS (BATS)

[randyw]

Originally Posted by 94-Newmar

Randyw, as mentioned above by the other posters, your friends new 30amp outlet is most likely wired for 220v, not 120v. It's very common to see this as most electricians see the receptacle and assume it's 220v - which of course it's not. I would suggest he, or someone, check that receptacle with a voltmeter to confirm. Nonetheless, as mentioned above, you most likely cooked your 12vdc converter and your microwave. Any 120v appliance that was not switched on will most likely be ok, but the microwave and converter have no on/off switch and are powered anytime AC voltage is present - which is why it cooked them.

94-Newmar: at this point I'm not too worried about the 30amp outlet as I won't he plugging into that outlet again. It was installed by an electrician, but the homeowner will get it checked. Is the 12 vdc converter part of the inverter or is it a unit on its own? The microwave might be ok as it still works when the inverter is on. It is surprising as we winterized the dishwasher while connected to shore power and it seems to be working fine. I suppose this will be a trip to the Newmar dealer.

Thanks for the replies.

[gfs1943]

Originally Posted by Jim T.

After you get your present problems fixed, you may wish to fabricate one of these to check any power pedestal before plugging in your RV.

Attachment 78616

Also, congratulations on buying the Progressive Industries EMS-HW50C. Good decision.




FMCA Local Chapter Secretary - Bay Area TravelerS (BATS)

Jim, do you have a diagram for your pedestal checker?

[Dutch Star Don]

Randy....I didn't see where you said other appliances were working in your first post. You only alluded to you got the washing machine winterized.

You need to determine exactly what's working and not working. Once you determine that, you can start looking as to what is feeding the items that don't work.

You said you reset the inverter. You should have a Magnum inverter. most of them have TWO resettable circuit breakers on them. You could lose half of the items if one has not been reset.

I would still take the cover off of the transfer switch, large black box in your power bay (they usually snap off) and take a quick look. If you fried part of the switch, there will be some obviously burned connections. It's free to check and will take about five minutes.

[randyw]

So, I took the cover off on the transfer switch. Notice a slight, not strong burnt odor. no other visible signs of over heating or burning. The LED on the circuit board is lit when genset is running, but not when hooked to 120v shore power.

Started the genset to test 120v circuits. Results are:
-Battery charger not working on shore-power or genset,
-AV & Sat systems work only on inverter,
-Micro works only on inverter,
-Heat pumps work on genset (didn't try on shore-power as only 15amp),
-Block heater works on Genset and shore-power,
-Dishwasher works on Genset and shore-power,
-Washer/Dryer work on Genset (didn't try on shorepower),
-Inside coach 120v receptacles work on inverter only.

Dutch Star Dan: Where are the resettable circuits on the inverter. I tried the reset method of holding the on/off button for 15 - 20 seconds, but it didn't seem to shut the inverter off let alone reset it. I read about a manual method which includes disconnecting the battery power and other steps. I might head there, but from what I see the inverter is working fine. Is the battery charger part of the inverter?

I've booked into the Newmar Dealer for next Tuesday, but would be good if I could narrow down the problem before then. I'm leaning to the transfer switch.

[94-Newmar]

The resettable breakers are located on the side of the Magnum Inverter. Depending upon how it's mounted, you may not see them - but once you do, they are unmistakable. They are pushbutton plungers, not conventional breakers as you would think.

Yes, the converter/charger is part of the Inverter in your case.

Unfortunately, it sounds like it may have toasted a number of things... at this point I'm not so sure I would even reset the breakers on the Magnum Inverter. Even if things begin to work their respective wiring certainly could be compromised due to the overvoltage they've experienced - and its probably best to have it inspected well before trying to bring the 120v side of things back to life. Having a "thermal event" isn't fun.

[tompen]

Just a note. I am one of those guys that wired the. 30 amp plug like a 220V and when I plugged in the motorhome nothing worked. You still only have 110V and the ground is missing. Just don't chase a red herring. The pedistal is probably not the problem.