In article .com,
wrote:
Can you get 120v single phase by picking off one line of 240v 3 phase
as long as you have a neutral to carry the current back to the box?

Not quite. The voltage won't be right for pure three phase. I
think that with Wye connections, you will have something closer to 104V.

And many are delta which *has* no neutral. All may be floating.

But a frequent variation has one of the three sides center
tapped (the way the standard residential feed is supplied, 240V center
tapped with the center tap grounded and neutral connected to that.)

The breaker boxes for this have three buses, but only two of
every three positions can be used for 120V single-phase breakers. The
third phase is *way* too high.

However -- from *any* reasonable 240V 3 phase, you can tie two
of the three phases to the primary of a 240-120V step-down transformer,
and power your equipment from that.

Enjoy,
DoN.

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