I just replaced my electric dryer with a gas unit. I now have an unused 30-amp circuit in my laundry closet. I would like to use this for some extra circuits. I don’t need the new circuit to be 30 amps. Can I install a small sup-panel with two 15-amp breakers and run two new circuits?
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Replies
You can if it's a 4-wire connection (2 hots/neutral/ground), but not if it's only a 3-wire connection.
Yes, if it's 3 wire than you should run the ground wire.
I am doing this myself in my garage, BTW. Extra stove circuit on a shared wall, so I am setting up a sub panel in my garage off that old line. I will have to run the new ground wire myself.
FYI, since that is a 30 amp at 220 circuit, you will have 60 amp total circuit capacity when you split it into the two 110 hots. That means you can use 20 amp breakers for the individual new subcircuits. Unless you plan on maxing out each breaker all the time, you can put in more than three since the total line it protected upstream of your subpanel.Rebuilding my home in Cypress, CA
Also a CRX fanatic!
The 10 gauge wire has four conductors. one black, one red, one white and a bare ground.
I will change out the breaker to two 20-amp breakers. The neutral and the ground will be shared. Can I put a junction box in where the socket is and run two 20 amp circuits out?
Should be OK, though the code lawyers need to weight in with the fine print. For everyone's future sanity, put some notes on a couple of gummed labels and put one on the back of the breaker panel cover and the other on the back of the junction box cover.You may need to "pigtail" the wires in the breaker panel, to get them to fit the breaker terminals.
If Tyranny and Oppression come to this land, it will be in the guise of fighting a foreign enemy. --James Madison
The details are too tedious to get into, but DON'T connec the neutral and ground i the sub-box. The ground should ground the new box; the neutral must be electrically isolated from the ground.
"The 10 gauge wire has four conductors. one black, one red, one white and a bare ground.
I will change out the breaker to two 20-amp breakers. The neutral and the ground will be shared. Can I put a junction box in where the socket is and run two 20 amp circuits out?"Yes, you have a classic example of a multi-wire circuit.Just remember that any connections in the neutral have to be pigtailed and cann't run through a receptacle (until you split if off into two sparate circuits).And unless you have one device (receptacle) with both hots on it you don't need a 240 breaker, you can use two separate single pole breakers.However, it is "better" to use the 2 pole breaker so that no one is surprised if they, for example, open the junction box.
Thank you all for your input.
Or replace the 30 A breakers with a pair of 20As and run all the 12 ga outlets from them you want. Use only a Single 20 A circuit if you only had 3 wires total.
Edited 4/25/2006 3:16 pm ET by junkhound