3 prong 50 amp hookups

[bearmangino]

[2018 Reflection 28BH]
Through some confusion an electrician has installed a 3 prong 50amp female plug on the side of my dads garage where we intended to spend a few weeks hooked up to his power.
I'm not especially good with electrical systems, but even I can tell that the male end of my 4 pole RV power cord will not fit into the 3 pole female outlet. It doesnt appear that my 30amp adapter would work either.
The electrician says he did everything right and refuses to fix it. Attached a picture of the outlet that was installed. Is this useable? An adapter maybe?

[Country Campers]

[2018 Reflection 28BH]
Through some confusion an electrician has installed a 3 prong 50amp female plug on the side of my dads garage where we intended to spend a few weeks hooked up to his power.
I'm not especially good with electrical systems, but even I can tell that the male end of my 4 pole RV power cord will not fit into the 3 pole female outlet. It doesnt appear that my 30amp adapter would work either.
The electrician says he did everything right and refuses to fix it. Attached a picture of the outlet that was installed. Is this useable? An adapter maybe?

No this will not work. The male end on the RV cord actually has 2 hot prongs , the 2 on the sides , one common and one ground. I have never seen an adaptor for this type. The 50 amp RV plug female is available at your local hardware store , Lowes , Home Depot and such. You will be much better off to have this replaced with the proper socket.

Brian

[ncitro]

[2018 Reflection 28BH]
Through some confusion an electrician has installed a 3 prong 50amp female plug on the side of my dads garage where we intended to spend a few weeks hooked up to his power.
I'm not especially good with electrical systems, but even I can tell that the male end of my 4 pole RV power cord will not fit into the 3 pole female outlet. It doesnt appear that my 30amp adapter would work either.
The electrician says he did everything right and refuses to fix it. Attached a picture of the outlet that was installed. Is this useable? An adapter maybe?

I’m not super familiar with twist lock receptacles, but I think that’s a 120v/240V 50 Amp Twist Lock receptacle. If so, then it’s the same as what’s on the end of your shore cord going into the rig. A simple mistake by the electrician, he’s probably just not familiar with RV wiring. If I’m right, then the right breaker is in the house, and the right size wire has been run, you just need the receptacle changed out to a 14-50R. That should not be a big deal for him. You could theoretically make an adapter, but it would be cheaper to just change the receptacle.

[Cate&Rob]

bearmangino
Although criticizing your electrical for not understanding "RV" 50A 240V seems to be the focus of most responses, it might help you understand why this has happened.

The outlet that he installed is (or at least should be) wired for 240V as would be used by a large machine such as a compressor or a welder. These devices use only the full 240V and do not need the voltage split in half for 120V devices as required for an RV. The outlet that you need for the 4 prong 50A RV cord has a 4th wire which is connected to the neutral bus at the panel and can divide the 240V into the two 120V circuits required by your RV.

The two "hot" leads (L1 and L2 in electrical terms) in the outlet that you have cannot supply the 120V circuits needed by the RV without adding a neutral (usually white) wire. An RV 30A adapter is indeed a 3 prong plug, but it must be plugged into a 120V outlet, not the 240V outlet that you have.

Rob

[ncitro]

bearmangino
Although criticizing your electrical for not understanding "RV" 50A 240V seems to be the focus of most responses, it might help you understand why this has happened.

The outlet that he installed is (or at least should be) wired for 240V as would be used by a large machine such as a compressor or a welder. These devices use only the full 240V and do not need the voltage split in half for 120V devices as required for an RV. The outlet that you need for the 4 prong 50A RV cord has a 4th wire which is connected to the neutral bus at the panel and can divide the 240V into the two 120V circuits required by your RV.

The two "hot" leads (L1 and L2 in electrical terms) in the outlet that you have cannot supply the 120V circuits needed by the RV without adding a neutral (usually white) wire. An RV 30A adapter is indeed a 3 prong plug, but it must be plugged into a 120V outlet, not the 240V outlet that you have.

Rob

Are you sure about that? I looked up the code on the plug (3P-4W) and could not find anything definitive, but I think the fourth wire is the ground on the outside of the plug like the shore cord on the rig. I assumed the 4W in the code was four wire. I assumed those three prongs were L1, L2, and N, and the metal outside was the ground.

I think it would be similar to this:

[tgodrich]

Are you sure about that? I looked up the code on the plug (3P-4W) and could not find anything definitive, but I think the fourth wire is the ground on the outside of the plug like the shore cord on the rig. I assumed the 4W in the code was four wire. I assumed those three prongs were L1, L2, and N, and the metal outside was the ground.

I think it would be similar to this:

I concur with Rob. A 50 amp RV has 4 connections; 2 hot at 120 V each, a neutral and a ground. On the Furrion receptacle on my trailer, the ground is the outer connection around the ring of the plug. The neutral provides the reference for the two hot leads, each of which is 120 volts. The Furrion plug on my Reflection is different from the regular RV 50 amp plug. But they both have 4 connections. Personally, I do not like the Furrion receptacle, but that is what came with my rig, so I make do. I have a 30 amp adapter to allow me to plug in to many of the RV parks that do not offer 50 amp service. I also have a 30 amp outlet on my RV pad next to my house.

30 amp will run one air conditioner and most all appliances. I run the fridge and hot water heater on gas when using 30 amp service, though. Plus the gas keeps the fridge colder than electricity. Neither the water heater or fridge use much gas. You can literally go weeks on gas for just the fridge and water heater.

[ncitro]

I concur with Rob. A 50 amp RV has 4 connections; 2 hot at 120 V each, a neutral and a ground. On the Furrion receptacle on my trailer, the ground is the outer connection around the ring of the plug. The neutral provides the reference for the two hot leads, each of which is 120 volts. The Furrion plug on my Reflection is different from the regular RV 50 amp plug. But they both have 4 connections. Personally, I do not like the Furrion receptacle, but that is what came with my rig, so I make do. I have a 30 amp adapter to allow me to plug in to many of the RV parks that do not offer 50 amp service. I also have a 30 amp outlet on my RV pad next to my house.

30 amp will run one air conditioner and most all appliances. I run the fridge and hot water heater on gas when using 30 amp service, though. Plus the gas keeps the fridge colder than electricity. Neither the water heater or fridge use much gas. You can literally go weeks on gas for just the fridge and water heater.

Yeah the “Furion” cord end and inlet on the RV are twist lock rather than the push on 14-50R receptacle used at the pedestal, I think because of the way it hangs off of the rig and because it’s more weather tight. I think that’s the same receptacle the electrician installed. If so then it’s a four wire install.

[tgodrich]

Yeah the “Furrion” cord end and inlet on the RV are twist lock rather than the push on 14-50R receptacle used at the pedestal, I think because of the way it hangs off of the rig and because it’s more weather tight. I think that’s the same receptacle the electrician installed. If so then it’s a four wire install.

I would much rather have seen GD put the receptacle inside the side compartment with an access through the bottom like the one for the water hose. That would be the most weather tight solution and do away with the need for the twist lock. It would also not require the power cord to hang from the side of the rig. I have toyed with the idea of that mod to my trailer and have the inside receptacle replace the outside one and just disconnect the outside one. There is enough leeway in the inside wiring I think this would work. On my rig you have to take off the cabinet door that is secured shut to get to the back of the Furrion receptacle.

[ncitro]

I would much rather have seen GD put the receptacle inside the side compartment with an access through the bottom like the one for the water hose. That would be the most weather tight solution and do away with the need for the twist lock. It would also not require the power cord to hang from the side of the rig. I have toyed with the idea of that mod to my trailer and have the inside receptacle replace the outside one and just disconnect the outside one. There is enough leeway in the inside wiring I think this would work. On my rig you have to take off the cabinet door that is secured shut to get to the back of the Furrion receptacle.

Getting beyond the OP issue (if you are looking for a good alternative to the twist lock look into the SmartPlug option, howson and I run those and I love it), my point is I think his electrician installed the same receptacle that is on the rig, which is a valid 125/240 VAC 50 Amp connector, and should have four wires run to it. If that is the case it should be simple to replace it with the correct 14-50R, either yourself if you are comfortable, or ask the electrician to come back and install that receptacle even for an additional charge.

I doubt there is any stupidity or incompetence here on the part of the electrician, just a misunderstanding to what was needed, and an unfamiliarity with what an RV needs. Sometimes we forget there are a lot of other electrical devices out there other than our rigs. This used to be a much bigger problem with the 30 amp receptacle as the "standard" was a 240VAC not the RV 30 amp receptacle. Now with the advent of 50 amp rigs it uses the more common 14-50R which is the same as an electric oven and even electric car charger uses.

[TucsonJim]

Here is a drawing of a properly wired RV 50 amp recepticle and the measured voltages that should be seen with a meter.

Do NOT try to find an adapter to plug your RV into the new outlet.

If your contract with the electrician was to install a 240 volt 50 amp circuit, he did what the contract specified.
If your contract with the electrician was to install a 50 amp RV circuit, he was in error.

[tgodrich]

Here is a drawing of a properly wired RV 50 amp recepticle and the measured voltages that should be seen with a meter.

Do NOT try to find an adapter to plug your RV into the new outlet.

If your contract with the electrician was to install a 240 volt 50 amp circuit, he did what the contract specified.
If your contract with the electrician was to install a 50 amp RV circuit, he was in error.

Note that Hot 1 and Hot 2 are 180 degrees out of phase. A properly wired plug of this sort will have to have two phases. This is AC voltage, the RMS (root mean square) value is 120 volts. The circuit breaker for this should connect to both phases. If it does not, you will only have 120 volts, not 240. Most all residential sub-panels have two phases available. The breaker will bridge across two phases. Note that Neutral and Ground are typically connected together at the main panel. The Neutral carries the current back to the source, the ground is non-current carrying unless a fault occurs. Neutral and Ground SHOULD NOT be connected together at the plug or receptacle. There must be 4 wires at the receptacle for the above to be wired correctly (some codes allow for downsizing the ground wire one gauge, but I typically wire all 4 wires the same gauge). If you are using a meter, use the AC setting.

As a personal safety note, never touch an electrical wire. AC voltage at 120 or 240 volts can be deadly. if you are not familiar with electrical wiring, it is best not to mess with it. If you must, make sure you shut off the circuit breaker, and measure with a meter to double check. You would be surprised how many homes have incorrect wiring. Mine was wired incorrectly at many places by the electricians who put in the wiring. The first thing I do in a new RV is check all AC outlets for proper wiring. A simple plug checker can be bought at Home Depot for about $10 and will also check the GFCI plugs as well.

[Cate&Rob]

Personally, I wouldn't trust anything that he did on the job....from the correct wire size to even tightening the screw terminals....much less putting in the wrong recept.

Assumes facts not in evidence. As noted earlier in this discussion, if the electrician was contracted to install a “50A 240V” circuit . . . that is what he did. If the electrician was contracted to install a “50A 240V RV circuit” then the criticism is justified.

Rob

[ncitro]

Rob, my question would be....why would any "Electrician" install something without at least asking the home owner what it was going to be used for. Granted, that wouldn't be necessary for let's say, a new recept. in the kitchen or bedroom, but a 50A 240VAC receptacle at a house (not a marina) should have brought out a questioning attitude as to what the homeowner needed. Then, on top of that, his refusal to even come back and try to make it right, shows his lack of care, concern, and craftsmanship. I don't believe anyone could argue against that point. The recept he put in would be totally useless in almost everyone's home....unless it was dockside at a private marina. He was simply more interested in doing a job, getting paid, and not caring whether the work was done correctly or to the customers satisfaction. He is a poor example of a true craftsman (which he likely isn't anyway) and at the very, very least, an example of how to NOT run a business.

Keep in mind from the OP it was not his home the work was being done at, it was his fathers. Could be the home owner didn’t really know, and wad a simple misunderstanding. We don’t know.

[Country Campers]

I do not understand why we are having a conversation on whether the electrician did the right job or not. We are beating this to the end.

The receptacle is not the correct one that will match up with the plug on the cord from the RV. There either needs to be an adaptor or the correct plug installed.

Hopefully the OP will reply with the fix.

Thanks all

Brian , moderator

[Cate&Rob]

Country Campers
Hi Brian,

I agree that this discussion has gone astray from what the OP asked. The important point is that there is no adapter that can make this outlet perform correctly for an RV.

Rob