In a prior post, the consensus was to “clean up” a circuit in my shop that was a combination of 12 G and 14 G wire. I have now run EMT for all outlets that were previously 14 G. From the outlet that had 12/2 IN and 14/2 out, I fished up to a new exterior mount box. EMT and exterior mounted outlet boxes now grace one wall of my shop. What wire to pull? I understand that I can’t use (or at least, should not use) 12/2 NM because of possible heat buildup in the emt. I have been told that I should use stranded. Is the only reason for stranded ease of the pull? Can anyone lay this out for me? Type of wire and the reasoning? Thanks
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THHN Solid in 12 ga with a 20 amp breaker.
One neutral and one hot. I never run a ground wire as the EMT, if done correctly, is your ground.
Some here may say the ground wire is needed but.....
Use the screw terminals, not the back stabs. I like to use a pigtail from the outlets to connect to the incoming and out going wires.
Make a shepard's hook with the stripped end of the pigtail and crimp around the screw before tightening. Wire nut the other end to the incoming and out going.
Not to sound condescending but watch the polarity on your outlets. Certain devices need it to be correct. The small slot or brass screw is your hot. Wide slot, silver screw is the neutral.
Make sense?
A good source for you would be the Taunton "Code Check: Electrical" book. It has the charts and illustrations for 99% of the things you need to know regarding electrical, in an easy to use format.
While stranded is easier to pull, solid is easy to push for short distances. Stranded may be tricker getting secure around a screw or into the back of a clamping outlet.
They also sell pigtail helpers - red wire nuts with a piece of stranded with a U connector on the end you can connect to the outlet on the screw. Makes it easy to do a secure connection.
NM cable can be installed in a conduit, as long as the conduit is sized properly. However, it's generally not done except if you need a short section of conduit as a sleeve for protection or to pass through a wall, etc. Plus, it's difficult to pull. There are a number of conduit sizing calculators on line, you can find them with a google search.
For a single circuit with 12 AWG wire (one hot, one neutral and a ground (as mentioned the ground isn't necessary with EMT but I'd include one - that's just my opinion) 1/2" conduit is fine. Either solid or stranded are acceptable, unless this is a very long pull I'd use solid as it's easier to get a good connection at the receptacle. Make sure you have no more than 360 degrees of bends in the conduit between junction boxes.
What JAlden said...AWG 12 solid, THHN insulation.
For residential work, I always run a grounding conductor. Especially in a shop/garage, surface mounted conduit may be seriously abused, and couplings come apart.
Cliff