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Wiring two single phase circuits to on three phase breaker

Thread starter #1
Hello everyone,

Not electronics but leads to one. I have a couple of VFDs that are wired to one 220VAC 3 phase - 20 AMP breaker which is more than adequate for both drives which require single phase 220VAC they 3 A each. They are basically wired to the same two phases of the three phase breaker.
But I got curious, would it make any difference and, specifically would it decrease the load on the breaker if the drives are wired to share only one phase and each would take a separate second phase. VFD1 phase 1 &2, VFD2 Phase 2&3 ?



Well-Known Member
You would balance the load across the two.
Are these specific 1ph only?, as many are dual 1ph OR 3ph.
Where are you that you have 220v 3ph supply? It is not all that common for a service.

schmitt trigger

Well-Known Member
Always strive to balance, as much as possible the loads of a three phase supply.

So to your question: "if the drives are wired to share only one phase and each would take a separate second phase." the answer is yes
Thread starter #5
Thanks Max and Schmitt.

Max, the drives are Schneider ATV12 series with model numbers ending with M2 and meant to be used for single phase. They have R/L1 , S/L2 and ground.
I'm in the Niagara region these days and that one plat has just about everything you can imagine in terms of hydro service.


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