I've been camping for decades and this is a new one for me. Just purchased a 2012 KZ fifth wheel with 50 amp service. When I first purchased it and plugged it into my house service via 20amp connection, all the outlets and devices ran properly. Then one day, only half of the outlets worked. Figured I messed something up UNTIL I camped at a campground with 50 amp service. Plugged it in and all was well. All outlets and devices worked. Next weekend I camped at a place with only 30amps. Plugged in using the appropriate 50am to 30amp plug and ONLY half of the outlets worked again. What is going on? Thanks!

Loose wire on one breaker. Makes and breaks contact?CHeck terminal at breaker panel. Pull on each wire see if one comes out of breaker screw.

I will go with your adapter being bad, also. Try a new adapter.

I did that. Same effect with three different adapters

I like the loose wire at breaker concept, but it's just so consistent. If I'm not on 50 amp only one side works.

Only 50 runs all outlets | Good Sam Community

26 Replies

bpounds
Nomad
Jun 15, 2016
It is a simple test on the adapter with a continuity tester. The two pins that are parallel with each other, on the 50A female adapter plug, should be connected together. Those also should both connect to the hot pin on the 30A male adapter plug.

Obviously nothing should be plugged in when doing this test. :)
CA_Traveler
Explorer III
Jun 14, 2016
If the 4th adapter doesn't work then it could be a intermittent problem anywhere in the 50A plug/cord or rig wiring and it just happened to be OK on the 50A pedestal.

Try wiggling the plug in various directions while checking for power on the dead leg. Next would be voltage checking until you isolate the open.
Chris_Bryant
Explorer II
Jun 14, 2016
wnjj wrote:
Chris Bryant wrote:
I thought of one other scenario that could explain that behavior other than bad adapter, but I really doubt it's the case- that would be a bad neutral in the rig- full 50 amp/240 vac service would give a virtual neutral, but the loads would have to be well balanced or the voltages would be all over the place.

Possibly...but I would think there would be nothing working while on the 30A service. Both hots of the 50A plug would be in phase with an adapter that supplies both from the 30A.

The only explanation that seems to make sense is an adapter that doesn't feed both hots.

Yeah- you are correct. I forgot that one leg does work...
It must be the adapter/cord interface.
wnjj
Explorer II
Jun 14, 2016
Chris Bryant wrote:
I thought of one other scenario that could explain that behavior other than bad adapter, but I really doubt it's the case- that would be a bad neutral in the rig- full 50 amp/240 vac service would give a virtual neutral, but the loads would have to be well balanced or the voltages would be all over the place.

Possibly...but I would think there would be nothing working while on the 30A service. Both hots of the 50A plug would be in phase with an adapter that supplies both from the 30A.

The only explanation that seems to make sense is an adapter that doesn't feed both hots.
Chris_Bryant
Explorer II
Jun 14, 2016
I thought of one other scenario that could explain that behavior other than bad adapter, but I really doubt it's the case- that would be a bad neutral in the rig- full 50 amp/240 vac service would give a virtual neutral, but the loads would have to be well balanced or the voltages would be all over the place.
wa8yxm
Explorer III
Jun 14, 2016
The 50-30 amp adapter is faulty, it's only powering one leg of the 50 amp service, Obtain a new one and all should be well once again.
camper1083
Explorer
Jun 14, 2016
Bpounds-the one you recommended was the one I bought. Hopefully that does the trick!
bpounds
Nomad
Jun 14, 2016
Just browsing the products and reviews on Amazon,

you do NOT want this one:
Adapter 1

this one appears to be wired correctly:
Adapter 2
starlord
Explorer
Jun 14, 2016
I think for the fifty amp you need the type that has the 30 AND 20 legs on it. The two leads going to the one fifty will give you enough to power the converter properly. I've had to use that type adapter several times over the last couple of years with no problems.
DrewE
Explorer II
Jun 13, 2016
1971duster340 wrote:
I've had the 20A GFI on the power pedestal not stay closed, but figured that was some phasing issue. That's using a 50A to 30A/20A Y adapter.

That's the GFI doing its job correctly. Those adapters by design create a ground fault (i.e. a return path for current from the 20A outlet other than its neutral).