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Can I use the 10 gauge wires (red, black, white, ground)from 30 amp, 250 volt dryer receptacle for two 125 volt circuits for two separate duplex receptacles? Can I use stranded wire for jumpers, or must I use solid wire?

  • Does the dryer need to continue in use? – Harper Aug 2 at 11:48
  • Dryer moved to other location – Robert Graf Aug 22 at 0:20
  • Sharing a neutral for 2 circuits is not a good idea. Overheating on that neutral galore if / when both those circuit reaches their max rated current. Not "cool".... Pun also intended. 🤔 – Retired Electrician Aug 28 at 2:25
  • Neutral wire now being used for 20 amp, 125 volt multi wire branch circuit, maximum 2,500 watts to each of two duplex receptacles, connected to double (dual-pole) 20 amp breaker. Previously, same neutral wire used for 30 amp, 250 volt, 7,200 watt four wire clothes dryer receptacle. Other than being divided between two receptacles instead of just one, wired exactly the same way. If overheating is still possibility, I must be doing something wrong. I would appreciate any input! – Robert Graf Aug 29 at 15:26
  • How can I add third ceiling florescent light and switch in garage to current system in which two switches control two lights? – Robert Graf Aug 29 at 15:42
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You could make a MWBC out of this /3 + gnd cable and install two 20 A receptacles. You would change the 2-pole 30 A breaker to a 2-pole 20 A breaker.

If the conductors are aluminum, you would pigtail with 12 AWG copper. If the conductors are 10 AWG copper, you might be able to connect these directly to the contacts on the receptacles.

I would make these to 20 A so that if you ever needed to run heavy current demand appliances, you'd have the capability.

EDIT To install a single duplex receptacle in the box, you would split the hot sides by breaking the connecting tab. The black wire would go to the hot side of one receptacle and the red to the hot side of the other.

The neutral side tab would be left intact.

  • My four-wire dryer outlet is connected to a 2-pole 40 A breaker. If I replace dryer outlet with two 20 A receptacles, (total of four outlets) can I connect them to two separate 20 A breakers? – Robert Graf Aug 3 at 20:43
  • Whoops! Am being told local code might require double (dual-pole) 20 A breaker, since receptacles share the same neutral wire. – Robert Graf Aug 3 at 21:39
  • Not just local code. National code. Also a physical requirement. Not "might" require. The two hots of a MWBC must be on different legs of the bus so the net current in the shared neutral is the difference in the currents in the two hots. What is the manufacturer of your panel? – Jim Stewart Aug 3 at 22:52
  • Using two duplex receptacles (giving four receptacles total) is not something I had considered. Can two duplex receptacles be installed in the current box? Would they fit and are there mounting holes? – Jim Stewart Aug 3 at 22:58
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    I ended up using thin copper washers under the screw heads for my braided pigtails. Tight secure fit with no strands sticking out from under screw heads as before. Am running free-standing room air conditioner off one of the new outlets. So far, so good, AC plug and face plate for outlets remaining cool to touch, no flipped breakers. – Robert Graf Sep 2 at 9:07
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Do you really need a split outlet? Why not just cap the red wire and use the black, white and ground. You have a 30 amp breaker that should be changed out to a 15 or 20 depending on the rating of the receptacle you're installing. Disconnect and cap the red wire in the panel, leave the breaker there so there are no open spaces in the panel. Install the new breaker in an available slot.

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    The OP might not have enough room in the original box for all the connections needed for a split duplex receptacle. In that case one might just cap the red as suggested. A person might never need two separate 20 A circuits at this one location. – Jim Stewart Aug 3 at 10:42
  • Actually I think I do have room for two receptacles. Each receptacle would have 20 A available, right? This would also give me a total of four outlets instead of just two. I like it! – Robert Graf Aug 3 at 21:35
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What you are trying to do can already be accomplished by existing adaptors. Here's an example converting dryer plug to split receptacle:

Adaptor

  • This is DANGEROUS. The result would be 15/20A devices running on a 30A circuit. I'd be shocked (pun intended) if UL would approve such a thing. It would be perfectly fine if it included a 20A breaker inside it, but I see no indication of that. – manassehkatz Aug 2 at 14:11
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    In addition, if you're doing the work yourself, the materials bill would be much less than what they are charging for this adapter. – PhilippNagel Aug 2 at 14:53
  • @PhilippNagel Actually, as a temporary fix (e.g., if there were no other circuits available and this was for temporary use to be switched back to the dryer later) this makes a lot of sense. The "only" problem is that it is dangerous. Same device with a 20A breaker would be safe & useful. – manassehkatz Aug 2 at 14:56
  • @manassehkatz, how is it significantly more dangerous than running a 1A device on a 15/20A circuit? That's something we all do all the time. (That's not a rhetorical or sarcastic question, I'm actually curious as to what the real danger is.) – Ray Butterworth Aug 2 at 16:08
  • What if you have a heater or motor that partly fails so that it starts pulling 25A instead of 15A. With a 20A breaker it will trip the breaker before the power cord overheats. With a 30A breaker it will never trip and cord or motor is more likely to actually overheat and start a fire. – manassehkatz Aug 2 at 16:33

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