Yes.
Use the red and white for one circuit and the black and white for another circuit.
The only restriction is that if you are installing duplex receptacle the breaker must be 15 or 20 amps. If it is higher then you can only install matching amp rated receptacle.

 

Yes, but the amperage of the circuit is important. If this is a circuit over 20 amps, you cannot use it for a 15 or 20 amp receptacle without reducing the breaker size. The wire is ok to use.

 

There are other questions about converting a US 220V circuit to 110V but I'm not certain of the terminology,

There are no such voltages as 220V or 110V in the US. Proper terminology is 240V and 120V

 

It will depend on the size of wire you have in place, now. If that was a higher amperage circuit, say for a stove , the wires won't fit a normal receptacle, no matter what you do to the breaker. Can you tell us the size of wire you are dealing with and the size of breaker it comes from?

 

It would also depend if the new circuits needed afci protection.

 

"220V outlet be changed to two 110V 3-prong outlets on the same circuit, without changing anything at the panel"

NO, the outlets would be on different circuits.

 

With a 4-wire 220V circuit, red and black both hot, and white neutral, and green ground, can the 220V outlet be changed to two 110V 3-prong outlets on the same circuit, without changing anything at the panel, by forking the white into two whites, forking the green into two greens so each outlet will have a neutral and a ground, and then supplying hot to one outlet with black and hot to the other outlet with red?

Yes, that's allowed but the rules aren't even that rigid. You can put any 120V outlet on pigtailed green, white and either black or red, your call. You can simultaneously put a 240V NEMA 6 or 14 type outlet on pigtailed green, black, red (and white if it uses that). There is no restriction saying you can only have 120V outlets or only have 240V outlets.

The only restriction, however, is the breaker must match the sockets as follows:

So you'll need to change the breaker accordingly. Note 15A sockets allowed on a 20A circuit, otherwise they must match. Also you can't do it with 40A or 50A circuits per 210.23. (some people say you can, to which I say good luck arguing with the inspector).

It will depend on the size of wire you have in place, now. If that was a higher amperage circuit, say for a stove , the wires won't fit a normal receptacle, no matter what you do to the breaker. Can you tell us the size of wire you are dealing with and the size of breaker it comes from?

They're planning to pigtail anyway.

It would also depend if the new circuits needed afci protection.

It's legacy wiring, which means AFCIs at the first receptacle should suffice. If the existing breaker is 15-20A I would argue that it's been a MWBC all along and nothing is really being changed that would trigger AFCI requirements.

"220V outlet be changed to two 110V 3-prong outlets on the same circuit, without changing anything at the panel"

NO, the outlets would be on different circuits.

NEC says when you have a shared neutral circuit, that's called a MWBC or Multi-[hot]-Wire Branch Circuit. "circuit" is singular. Another way of thinking of that is when counting circuits, count neutrals.

Also note the handle tie requirement. If the circuit serves 120V and 240V loads both, it needs common trip, so a 240V breaker not handle ties.

 

They're planning to pigtail anyway.

I missed that post where he said that.

 

Thanks for all the replies. It is AWG 12 3 CDR Romex with GROUND. It's in metal conduit in my garage and was used for a couple of vintage 220V woodworking tools that I've sold and will be replacing with 120V tools.

 

You will have to do something at the panel if a neutral wasn't used for the previous loads. You would land it on the neutral bar. Make sure the 2-pole breaker is 15 or 20A. If you have Romex, you most likely won't have a green ground, it will be bare copper. Now having said that, there used to be some Romex years ago that had a smaller ground with green insulation.

 

Once the wires exit the conduit they will not have any nomenclature printed on it, such as THWN. In addition the wires in NM-B are not waterproof necessarily and conduit is considered a wet environment.

 

Here is the 100A subpanel, which shows black+red pairs and the whites connected to the neutral bar. Upstairs in the kitchen, if I remove some cabinet drawers, there is a junction box on the wall. There the red wires are connected to the black wires that are pulled through the brick wall into the narrow box shown in picture #1 above.