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Help;/30amp 50 amp 125volt 3 pole 4 wire? Do you smell something burning too ?

June 13, 2011, 11:42:42 am

I blew my converter charger. Its a triad_ utrad  in a 1986 Beaver.
When I got my RV  the owner before me had it plugged into just a regular wall outlet.
 
It had what I think is called a flip flop adapter that adapts a 30A, 125 power cord to a 15a, 125v power source.
The converter/charger made by      hummed loud all the time when plugged in.

Even I knew this set up was not a good idea! So I asked by brother in law First big mistake:) about hooking up a proper 30a power source to plug the Rv in to!

So with a 30 Amp breaker in hand and fear in my heart, I opened the breaker box, shut off the power, ran my new lines to the box and hooked in my two hot leads and the ground. The other end got a  female plug from Lowe's that said 30A.

I plug it all up and head into the RV to run both A/c at once to see how she does.

Heading in, I hear right off that the hum is gone for the converter and can see that the 12v system is not working. I checked and the breaker is tripped for the converter charger.  And if I reset it, it trips immediately.

That's when I start to back track and see a lot of problems.

First thing, I pick up on is that there is a sticker that says.
"This connection is for 120~140 volts 3 pole 4wire 60HZ  50 Amp Supply"

Above that is obviously not an original female inlet connector.
 It says "Marinco easy lock 50A 125/250 V Grounding"

That's not matching

Second problem I see is that the large cable that plugs into the Rv  matches that Marincio 50A on the end that plugs into that but the other end that connects to the power supply is only a 30a 125v.

That's why I hooked up the 30a breaker and not a 50a.

So I check things with the multi meter. If I go from left hot to ground I get 120 Volts Right side to ground 120 volts!
Right to left 240 volts.

I have a feeling that's too much but it says 240 on the sticker. I know that the 30A connections need to be changed to 50 but I have a feeling that's just the start of getting this done correctly.

Advice, questions, comments, concerns?  Any suggestions on a reasonably priced  converter charger?

I have included some pictures so you can see what I am working with.

Thanks so much,
Tony

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Re: Help;/30amp 50 amp 125volt 3 pole 4 wire? Do you smell something burning too ?

Reply #1 – June 13, 2011, 12:40:15 pm

Tony,

Looking at the photos, it's likely the wrong 30 Amp breaker and wiring were installed.  30 Amp for an RV is single phase 120, not two phase 240 (like for clothes dryers).

This website has good info regarding a proper 30 amp RV installation (and also 50 Amp)
RV Electric

If that's what happened, you wouldn't be the first (small comfort, I know).  Hopefully it's just a blown converter (and the cost of installing the correct circuit and receptacle)

Michelle

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Re: Help;/30amp 50 amp 125volt 3 pole 4 wire? Do you smell something burning too ?

Reply #2 – June 13, 2011, 02:16:12 pm

Tony,

Sorry, about your problem.  You might get lucky with the converter if its just a blown fuse somewhere inside the converter.  That was the case with me after an accidental 240 connection to an improperly wired outlet.  For about 2 weeks the inverter/charger was dead, I was bidding on used ones on ebay and not winning.  Finally found a very small 1/2 amp fuse that was blown, replaced it and it worked like it should.  Just for your information when plugged into a 50 amp receptacle 240 does get delivered to the electrical box in the coach, but nothing in the coach is wired so that 240 is used.  When plugged into 30 amp or less the dogbone adapter has to be used and the internal wiring of the dogbone sends 120 into both hot legs of the 50 amp cable.  Everything in the coach is powered, but you can only use a few things at a time or the 30 amp cable will be overloaded.  And if plugged into 15 amp maybe just the converter is available if it's not pulling more than 15 amp. 

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Re: Help;/30amp 50 amp 125volt 3 pole 4 wire? Do you smell something burning too ?

Reply #3 – June 13, 2011, 08:23:42 pm

Tony, I think both previous posts are on track. When you installed the 30 amp breaker, the black wire from your new wiring should have gone to the main, hot leg, the white wire to the neutral bar and the bare copper ground to the ground bar where the other bare copper wires are anchored. This would have given you 110/120 volt electricity. It sounds like somehow you attached the black wire and the white wire to the another breaker on the main. If you had a double thirty breaker you did not need it. You needed only a single 30.

I hope your converter is not blown and you very well may have issues with your automatic transfer switch but I trust you will be able to repair any damage inexpensively. I certainly understand working on a budget.

I hope I am explaining this clearly and properly. I certainly am no professional electrician. You will probably get more clear and accurate responses from those better trained than me.

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Re: Help;/30amp 50 amp 125volt 3 pole 4 wire? Do you smell something burning too ?

Reply #4 – June 13, 2011, 09:19:05 pm

OK, the correct wiring at the house end to supply a PROPER, REPEAT PROPER 50 amp RV is:

TWO hots, L1 and L2 (240 VAC as measured between them)
ONE neutral (probably missing in an older house 30 amp dryer plug which may be the one in one of your photos)
ONE ground

Best (and proper wiring) if each of the hots is wired through a 50 amp breaker.  So the pair of L1 and L2 would have a 50 amp duplex breaker.

Yes, particularly if the wiring is not sufficient for 50 amps, you could use 30 amp breakers, BUT the wiring has to be as above and your total power consumption would be limited to 60 amps (2 30's) vs 100 amps (2 50's).

Your coach 120 VAC breaker panel puzzles me-- it shows two 30 amp main breakers (assuming your photo is of the top/main breakers).  That is definitely NOT proper for a 50 amp RV, which is what your RV power inlets show?

You need to get with someone familiar with RV wiring to determine how your coach is wired and therefore what power needs you have.

Brett

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