[Perry401]

I have a friend who owns several rental properties. He has had issues with renters who bring their own dryers. If the house has 3-wire dryer outlets, the renters need a four wire outlet. If the house has a 4-wire dryer outlet, the renters need a three wire outlet. He could make the renters change their cords, but some would do this themselves and perhaps do it wrong. He also had one renter change the outlet himself, and didn't realize it until after the renter moved -- again, a potential safety issue if it was done wrong. Some of his renters are elderly, or on some form of subsidised housing, and bring dryers from their old houses, or buy used appliances.

He ask me if it would be permissable to install one of each time of outlet at the dryer location, keeping the single feed from the breaker box. I have never seen this done, but can understand why he wants to do it. He does not want to run a new feed from the panel to the second dryer outlet, simply put one of each type at the end of the existing runs, which were upgraded to 3-wire with ground in all houses.

 

[frenchelectrican]

I will not bother with two dryer recepatles at all it kinda defeat the safety purpose.

If you ahve 4 conductor cable or conductor in there then go with 4 wire receptale all by the means

If you have 3 conductor cable use the 3 wire receptale however if you have soild bare ground conductor that is a major no-no on that one.
I have see some older dryer circuit use the 10mm²(#8awg) SE cables so it kinda pretty common that time.

I have deal quite few rentals and I always go with 4 conductor setup all the time as long the cable or have full 4 conductors in there.

4 conductors mean Red et Black et White et bare or green conductos.

However becarefull when you change from 3 to 4 wire set up on dryer please pay attetion the way the frame bonded to the netural connections I have ran into couple dryers if you see green wire screwed to the frame some case it can be neutal bond so check it out with simple DVM to ring out if that the case or not. If bonding strip or jumper wire just bend it back or discharge it.

Merci,
Marc

 

[mpoulton]

That's a really great idea, actually. It will require adding a j-box to split the feed between the two receptacles. I could be wrong, but I believe it is not technically code compliant to feed two such receptacles from one circuit, but in this case I would do it anyway.

An easier and probably cheaper option would be to install 4-prong receptacles everywhere, and make 4-prong to 3-prong adapters using a 4-prong dryer cord and a 3-prong cord-end receptacle. It might be considered unwise to make adapters that go the other way.

 

[Speedy Petey]

I could be wrong, but I believe it is not technically code compliant to feed two such receptacles from one circuit, but in this case I would do it anyway.

I believe you are sir.
How is this any different from a standard 120v/20a circuit and receptacle(s)?

We do this with commercial welder circuits all the time.

 

[Perry401]

I had not thought of Mpoulton's suggestion of a short adapter cable, but question if it would be legal. As I understand him, all outlets would be wired as 4-prong. Then a short 4-prong male to 3 prong female adapter would be provided to tenants who have 3-prong dryers. It seems like if an adapter was a good way to go, someone would make one that you could buy off-the-shelf.

Use of an adapter would seem in some ways like an extension cord or temporary wiring, which might not meet code for permanent (or at least "stationary") equipment. I would also be worried about the liability if a field-fabricated adapter cable was damaged or otherwise failed. Using an adapter would also create a situation were you would have two plug and socket connections instead of one to fail, or be connected loosely.

As far as two "heavy" outlets on one circuit, I too have seen this in commercial environments for things like welders. I worked 30 years in industrial control and many machine builders did this not only for their welders, but also to provide plug-in points to test and repair customer equiment. In this case, the application was temporary in nature -- a few weeks in the worst case. Equipment was built or came in which required different connector cords to meet the customer's requirements. Having a wall of different connectors let the machine builder work on the equipment without having to rewire the main power supply cable or run a temporary feed to the machine's disconnect switch. But commercial and residential environments are different.

I have checked 2008 NEC as best I can and have not seen any rules one way or the other. It is a dedicated circuit and but would be protected by the 30 Amp breaker, so if two loads were attached which took too much current the breaker should pop.

Does anyone know if two outlets would be permissable by code or reference sections that would prevent this from being done?

 

[SD515]

I have checked 2008 NEC as best I can and have not seen any rules one way or the other. It is a dedicated circuit and but would be protected by the 30 Amp breaker, so if two loads were attached which took too much current the breaker should pop.

Does anyone know if two outlets would be permissable by code or reference sections that would prevent this from being done?

I have not found anything either, other than installing 2 receptacles would no longer classify it as a individual branch circuit, it would be a multi-outlet circuit.

 

[Cow]

Since he has 4 wire dryer receps now, you can't legally add a 3 wire dryer recep.

Make the renters change their cords, that's the right way to do it. If he's scared of them doing it themselves, maybe he should tell them to call an electrician!?!?!

You match the cord to the recep, not the recep to the cord.

 

[frenchelectrican]

I believe you are sir.
How is this any different from a standard 120v/20a circuit and receptacle(s)?

We do this with commercial welder circuits all the time.

I know with commercal welder it is common to do that however with the OP part he stated for both tri and quad wire dryer receptale then IMO it is not a good mix at all.

Merci,
Marc

 

[Speedy Petey]

I know with commercal welder it is common to do that however with the OP part he stated for both tri and quad wire dryer receptale then IMO it is not a good mix at all.

Merci,
Marc

Marc. I wonder why you say this?
Especially considering it is going to be behind a residential dryer that is transient. Meaning each new tenant will bring in their own dryer.
The two will NEVER get used at the same time.

As long as a dryer does not draw more than 24A (it will not) to satisfy 210.21(B)(2) & 210.23(B) it is fine.

The more I think about it the more I love this idea for a rental unit.

 

[Perry401]

Since he has 4 wire dryer receps now, you can't legally add a 3 wire dryer recep.

Can you site NEC section that says this?

 

[frenchelectrican]

Marc. I wonder why you say this?
Especially considering it is going to be behind a residential dryer that is transient. Meaning each new tenant will bring in their own dryer.
The two will NEVER get used at the same time.

As long as a dryer does not draw more than 24A (it will not) to satisfy 210.21(B)(2) & 210.23(B) it is fine.

The more I think about it the more I love this idea for a rental unit.

Pete.,

Thanks for bringing the 210.23(B) up somehow I miss that part and I have done litttle research myself and as long the exsting cable or conduit have grounding conductor in there then it will work either way.

I did do little checking on French side and it can be done simair way as well.

Merci,
Marc

 

[Speedy Petey]

can you site nec section that says this?

250.140

 

[nap]

due to 250.140 exception, you cannot install a 3 wire recep if there is a grounding conductor present, so, if there is already a 4 wire circuit ,you cannot install a 3 conductor recep

then, if you have a 3 wire circuit, you cannot use a 4 wire receptacle because you cannot wire it per listing using only 3 wires since this would require bonding the ground and neutral of the recep



what you do is put it in the lease that there is either a 3 wire or 4 wire receptacle (whichever there is) and the tenant is not allowed to alter the wiring of the house, ever.

in addition, if a dryer is installed, the installation must be approved by the LL.

Any violations will result in taking their walkers away from them.

 

[Perry401]

Thanks everyone for the feedback! I have shared it with my landlord friend. He will change any existing 3-prong outlets to 4 prong as required by code, and for existing tenants change over the cord sets as needed. He will change the lease to require 4-wire only dryer cords.

Funny thing is that his locally licensed master electrician has been swapping the outlets back and forth for years without knowing any better. He has also been clued into the code requirements.

 

[Speedy Petey]

Funny thing is that his locally licensed master electrician has been swapping the outlets back and forth for years without knowing any better. He has also been clued into the code requirements.

Don't tell me. He got his license 25 years ago and has not looked at a code book since? :laughing: