Outlets and Wire Gauge? - Please help!


I finally contracted an electrician to run two dedicated lines - a week from today! I have been reading thread after thread and the consensus appears to be going with 10awg wire for the 20amp run. My problem is two-fold:

  1. I'm stuck selecting an outlet because the electrician says that no 20amp outlet can take 10awg, that "10awg is for 30amp outlets".
  2. I'm stuck selecting an outlet because of what it might do to my sound. 

I simply want to install something good that's going to feed a Puritan Audio PSM156. I am now running ADG Gran Vivace monos. I prefer a rich midrange.

Additionally, I asked for both a 15 and 20 amp run. People suggested I do this so my sources can be run off the 15A with amps / subs off of the 20A, but someone here mentioned ground loops? I am not well-versed in things electrical. Ideally I would like to know if I should stick with the two runs, and what would be a few good choices for each outlet if I do. @jea48 @erik_squires ... I have seen solid advice from you on the topic of outlets, but they lack things specific to awg and outlet type.

Thank you in advance!

PS I estimate the length of the run to be approximately 50', max.

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I would send your electrician back to electrician school.  10 AWG is fine for a 20 Amp receptacle.  In some situations it would be considered overkill but a determining factor is the length of the wire run.  Depending on how long the wire run is, it may be preferred because of less resistance and voltage drop.  For a 50 ft run, I would definitely go with 10 instead of 12.  

10 AWG to a 20A receptacle is fine.

The electrician is pushing back (likely) because 10 AWG is more expensive, more physically difficult to work with, not something they normally do, and frankly, overkill.

That said, it's your money, you're entitled to get what you want as long as it's safe/legal. If he's not amenable to this, find another guy.

This is just basic outlet wiring practices and how to follow electrical codes.

A 15-amp circuit should be wired with 14 ga. only.  Using larger ga. wire is a fools errand.  In this situation, you can basically overload the circuit and not trip your protective circuit breaker in your service panel.

A 20-amp circuit should be wired with 12 ga. only.  Same thing applies as above.

Whether or not an outlet can physically be wired with a larger conductor/gauge wire is unsafe and is an electrical code violation.

Using multiple outlets to the same room location on different circuits is an invitation for ground loops.  In an attempt to avoid ground loops, you should locate those circuit breakers on different bus locations in your service panel prior to finalizing their locations.  You may need to re-arrange them, so leave the service panel cover off until you ensure that you don't have a ground loop.  If/when you are successful, then you can break-off the service panel breaker covers at their finalized locations.

Just because someone else wires their breakers/outlets with oversized wire doesn't make it right.

@perazzi28 your information is wrong, you can use 10awg wire with a 20 amp breaker, the breaker is what makes it safe not the oversized wire. I have 10awg wire on 20 amp breakers with 20 amp outlets and this passed inspection.

... you can use 10awg wire with a 20 amp breaker, the breaker is what makes it safe not the oversized wire. I have 10awg wire on 20 amp breakers with 20 amp outlets and this passed inspection.

Absolutely true and my dedicated outlets also passed inspection. One definite advantage to derating the wire (such a s 10AWG on 20A line) is it reduces voltage drop. That’s especially useful if it’s a long run between panel and receptacle.