just wondering if anyone has seen a problem coming from the transfer switch when on 30 amps, I have several recepticles out , but when running the genny everything works fine. I don't have a 50 amp line at home to plug it into, so I don't know if it will do the same thing

It sounds like one of the legs is not being connected for some reason. While it's possible that there's a contact in the transfer switch that is failing to make contact, there are also other possibilities to check.It could be that your 30A to 50A adapter is broken and not supplying one of the two 50A legs with power. That should be pretty easy to check with a meter. It could also be that you have a broken connection at your shore power plug, or at the other end somewhere.

A Learning Moment For Mex...With 240/50 rigs, is it a universal practice to enable all and everything but additional roof air conditioners when running on a single 120 vac leg? How is the shed of A/C power accomplished?Thank You

DrewE wrote:It sounds like one of the legs is not being connected for some reason. While it's possible that there's a contact in the transfer switch that is failing to make contact, there are also other possibilities to check.It could be that your 30A to 50A adapter is broken and not supplying one of the two 50A legs with power. That should be pretty easy to check with a meter. It could also be that you have a broken connection at your shore power plug, or at the other end somewhere.I really don't know. on our previous mh, which is in salvage heaven, when ever I plugged it in , 30 or 50 amp service it always worked great. I think you are right, thats what I have been thinking. plus i am not using any adapters. i think the relay in the box does the thinking

MEXICOWANDERER wrote:A Learning Moment For Mex...With 240/50 rigs, is it a universal practice to enable all and everything but additional roof air conditioners when running on a single 120 vac leg? How is the shed of A/C power accomplished?Thank YouThe typical practice, as I understand it, among less fancy units is to leave load management entirely up to the user. The adapter (or 30A cord) just applies the single 120V hot to both legs of the main breaker, so every circuit has power. (Obviously any actual 240V circuits would not operate, but they are quite rare. I guess some clothes dryers used in RVs are 240V, but that's about it. Many 50A RV load centers can't accommodate 240V branch circuits at all.)Fancier coaches with a full-fledged EMS use various load shedding setups, the details being I suppose mostly at the whim of the manufacturer.

Start by verifying that your adapter's female end (30 male to 50 female) DOES have 120 VAC between each outer straight and the center straight and center round. Zero center round to center straight.Let us know what you find.

transfer switch 50 amp | Good Sam Community

23 Replies

DrewE
Explorer III
Nov 14, 2017
time2roll wrote:
AH HA!!!

Need to jump 30 amps to the other blade (#10 wire) or half the RV will remain unpowered.

Even better pop in a double 30a breaker and pull a new hot to the other blade.

Neither of these three options is up to code afaik. Need 40 amp or 50 amp 240/120 split phase power to meet code. Still technically safe either way.

I think the code permits one to use oversized outlets for circuits, though I'm not 100% certain about that. Going the opposite way is of course not permitted, with the one (very common) exception that multiple 15A 120V outlets may be placed on a 20A 120V circuit.
wolfe10
Explorer
Nov 14, 2017
Yup, you have created your own problem.

30 amp has a SINGLE HOT. 50 has TWO HOTS.

So, jump from the single hot in the outlet to the other outer straight. That does exactly the same thing as a 30 to 50 adapter.
time2roll
Nomad
Nov 14, 2017
AH HA!!!

Need to jump 30 amps to the other blade (#10 wire) or half the RV will remain unpowered.

Even better pop in a double 30a breaker and pull a new hot to the other blade.

Neither of these three options is up to code afaik. Need 40 amp or 50 amp 240/120 split phase power to meet code. Still technically safe either way.
billyboy
Explorer
Nov 14, 2017
time2roll wrote:
OK so you must be using an adapter to put a 50 amp plug into a 30 amp supply.
30 amp is 3 pins and 50 amp is 4 pins. Or is this something else?

Check that the adapter is putting power on both hot pins. Then check if both the main breakers have power.

Then you have the inlet connection and the transfer switch to check.

I have a 50 outlet that is only wired for 30 amp, that way I can plug the big power cord into it, but it only has 110 on one blade.
MEXICOWANDERER
Explorer
Nov 14, 2017
LOAD SHED

A protocol in which loads can be divested according to a pre-arranged sequence

a) prevention of application of a circuit overload by virtue of nulling the power source. Can be enacted for any pre determined condition.

b) elimination of a load for security (volts, amps, etc)

By automatically shedding a circuit, power is eliminated before load could be applied. Dead circuit.
time2roll
Nomad
Nov 14, 2017
OK so you must be using an adapter to put a 50 amp plug into a 30 amp supply.
30 amp is 3 pins and 50 amp is 4 pins. Or is this something else?

Check that the adapter is putting power on both hot pins. Then check if both the main breakers have power.

Then you have the inlet connection and the transfer switch to check.
billyboy
Explorer
Nov 14, 2017
time2roll wrote:
billyboy wrote:
just wondering if anyone has seen a problem coming from the transfer switch when on 30 amps

billyboy wrote:
But I am not using any adapters, I am just plugging in with the heavy 50 amp power cord
OK so is it 30 or 50?

I am plugging into to a good 30 amp box . The unit is a 50 amp m.h.using the 50 amp power cord that came with it.
billyboy
Explorer
Nov 14, 2017
time2roll wrote:
billyboy wrote:
just wondering if anyone has seen a problem coming from the transfer switch when on 30 amps

billyboy wrote:
But I am not using any adapters, I am just plugging in with the heavy 50 amp power cord
OK so is it 30 or 50?

I am plugging into to a good 30 amp box . The unit is a 50 amp m.h.using the 50 amp power cord that came with it.
time2roll
Nomad
Nov 14, 2017
billyboy wrote:
Ok, I am not getting any currant to either gfi box at all, with the boxes out of the wall to look for current.
Do you have voltage on both main breakers? Assuming you do check each branch circuit has voltage coming off each breaker.

Or if one of the mains is dead you need to work back to the transfer switch to verify voltage on both sides.

Keep moving along until you find the open connection.
time2roll
Nomad
Nov 14, 2017
billyboy wrote:
just wondering if anyone has seen a problem coming from the transfer switch when on 30 amps

billyboy wrote:
But I am not using any adapters, I am just plugging in with the heavy 50 amp power cord
OK so is it 30 or 50?