400HZ- 120Y & 208V Circuits

[faresos]

Hello Everyone:

I'm working on a project (Avionics) where the client is requesting a 120V-single phase and 120Y-3-phase. I'm a little confuse with the 120Y-3-Phase terminology, do they mean 208Y-3-phase? is there anything such 120Y-3-phase in the 400HZ power distribution world? I looked at the existing facility and the 3-phase circuit is fed from 3-poles breaker.

Thanks,

 

[drcampbell]

I'm sure that's what they mean: three phases, each of which is 120 volts to the common center tap.

Most of the 400-Hz aircraft circuits I've seen have been 115Y200 volts, but I doubt the distinction is terribly significant.

 

[kwired]

Most likely is three 120 volt coils connected in wye and has 208 between outer ends.

No experience in these applications - may be possible there just isn't any loads that operate at 208 volts and they simply refer to it as a 120 volt source because all loads are 120 volts?

 

[petersonra]

It is probably a 3 phase system - 200V L-L and 115V L-N.