3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
(OP)
I like to know whether it is technically correct to provide a 3-phase 4-Wire panel from a residential single phase panel which I assume which has L1 and L2 and a Neutral.
I was asked to provide a 60 amp sub-panel form a residential panel which I assume 100 Amp or larger. I had a choice of providing a 60 amp single pole breaker in the residential panel to feed the 60 amp sub panel OR provide a 30 amp three pole circuit breaker to feed the 60 amp sub panel.
I am confused as to whether it is technically correct in providing a three pole 30 amp circuit breaker to feed the 60 amp sub panel. The 60 amp sub panel may have five 20 amp circuits totals less then 40 amps. Unfortunately I didn’t have a chance to make a site visit to this moment.
Thank you in advance.
I was asked to provide a 60 amp sub-panel form a residential panel which I assume 100 Amp or larger. I had a choice of providing a 60 amp single pole breaker in the residential panel to feed the 60 amp sub panel OR provide a 30 amp three pole circuit breaker to feed the 60 amp sub panel.
I am confused as to whether it is technically correct in providing a three pole 30 amp circuit breaker to feed the 60 amp sub panel. The 60 amp sub panel may have five 20 amp circuits totals less then 40 amps. Unfortunately I didn’t have a chance to make a site visit to this moment.
Thank you in advance.






RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
A 30amp 3ph circuit breaker should NOT be used from a 1ph panel to supply 60a 1ph load.
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
As I have indicated I also had choice of using a 1-pole 60 amp breaker to feed the sub-panel, which will work I am sure. Also as I have mentioned, I have not had a chance to verify the main panel in person, so the thread was again "what if"!
Thaks for all your info, I have decided to use a 2-pole 30 amp brekaer to feed the sub-panel. I am sure this will work.
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
Reversed polarity vs. 180 deg. out of phase.
When I hear the single, center-tapped transformer winding supplying a single phase service referred to as "180 deg, out of phase" I think that it is akin to calling two batteries in series, supplying 12 and 24 volts, "180 deg. out of phase" with each other.
respectfully
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
Have you got a better way to shorthand explain the split-winding grounded-center-tap one-phase connection?
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
Is 'The two hot lines are in anti-phase' any better?
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Sometimes I only open my mouth to swap feet...
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
Mike Halloran
Pembroke Pines, FL, USA
RE: 3-Phase 4-Wire Sub Panel panel form a 1-Phase Risidental Panel?
Am I coming off and a Trekkie geek?