Re: 14ga 15amp. Vs 12ga 20amp wires and outlets
First, if you use 14ga wire in the circuit then the breaker is limited to a 15 amp breaker so you need to stick with 12 ga. The breaker is sized to the lowest rated unit in the circuit.
Second I would use 20 amp receptacles, they will work with standard plugs and be able to handle 20 amp plugs on heaver shop equipment.
Third Yes you can use 12 ga wire on 15 amp receptacles, just make sure you use the screws and not the back stab connections.
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