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A comment on Why does the USA use 110V and UK use 230-240V?. Parent comment

Re:Why does the USA use 110V and UK use 230-240V? by thsksbd on Tuesday August 29, 2023 @03:58PM (#37313069)
It has nothing to do with efficiency (do the math on the conductor gauge and it all mostly cancels out) or power (idem) but the types of motors used (squirrel cage I believe).

The problem is getting the motor to start spinning. You cant start all motors on just one or two phases. And if a motor isn't spinning, it's essentially a short.

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Re:Why does the USA use 110V and UK use 230-240V? by midoridensha on Wednesday August 30, 2023 @06:01AM (#37319645)
No, very large single-speed industrial motors are synchronous motors, not squirrel-cage (induction). These motors cannot start spinning on any number of phases: they can only run at the synchronous speed (which is dictated by the power line frequency and the number of poles in the motor). And it's not a short; it just doesn't run at all if you supply power to it; it only works once it's at the synchronous speed. These motors are used because they're the most efficient type of AC motor. Induction motors have "slip" of around 3% IIRC.
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