On 12/4/2019 8:30 AM, trader_4 wrote:
....

A 240V breaker sits across both hot legs. I doubt it's code compliant
to use just half of it for a 120V circuit, but IDK. Fretwell?

Isn't. No dedicated neutral to the circuit that way.

Only (used to be but even it isn't allowed any more) was the 3-wire
service for dryer-like appliances with the ground serving as secondary
110V circuit neutral. That now requires 4-wire, not just three.

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