I have a 240 circuit that i am trying to split into 2 120 circuits. I have only 3 wires available, red/white/black. I have another circuit a few inches away (both in junction boxes), Can I share the GROUND wire with the two circuits to avoid having to run all the way back to the panel or getting only one circuit from the 3 wires. I know how to split the circuit, breakers, etc. My only question is the shared ground. All 3 circuits will be 20A.

It is the GROUND I am asking about, not the neutral wire.

  • Are the cables of the 240V circuit inside metallic conduit or tubing for the full run? You may have different options depending on this answer since the circuit may already be already be grounded by the conduit. Also, just in case: You cannot "split the breakers" if you are going to use a common neutral (white wire) for the two circuits. You will need to get a double-pole 20A breaker if you plan to use the same neutral for both circuits so that you (or someone else) doesn't turn one circuit off and mistakenly think there's no possibility of current running through the shared neutral anymore. May 18, 2016 at 16:43
  • Your question was understood and still has an answer at the duplicate question. My comment regarding the neutral was in relation to your statement about knowing what to do in terms of splitting the breakers since technically you wont be splitting the breakers, but rather you would need to install a single "tandem breaker" for the two new circuits you'd be creating. Like I said, you probably already know that, but I figured its better to say it just in case rather than have someone accidentally electrocuted by a live neutral wire when they think one of the new circuits is turned off completely. May 19, 2016 at 23:04
  • My wiring is Non Metallic (not in conduit) and I do have a tandem breaker. I would plan to use the neutral for both circuits. May 20, 2016 at 0:35


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