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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default A basic 3-phase question

On 01/03/2020 13:37, AnthonyL wrote:
So in the coffee bar this morning chat pondered on 3-phase and how to
know which of the 3 wires was which phase. I've done some googling
and would like the experts to confirm:

1. It doesn't matter which wire is which phase providing the sequence
of 1-2-3 2-3-1 or 3-1-2 is maintained when connecting, or any pair
swapped if that is what is required.

2. The voltage between any two phases is 440v and it doesn't matter
which two

and

3. The voltage between any phase and ground/neutral is 240v

Is that correct?


yes


Are there any conditions when the phase needs to be known? If so how
is it detected?

The only time you need to know is when connecting to a true AC motor
when reversing any two phases will reverse the motor direction






--
Future generations will wonder in bemused amazement that the early
twenty-first centurys developed world went into hysterical panic over a
globally average temperature increase of a few tenths of a degree, and,
on the basis of gross exaggerations of highly uncertain computer
projections combined into implausible chains of inference, proceeded to
contemplate a rollback of the industrial age.

Richard Lindzen