Hi-Leg Delta 4-Wire Receptacle

[Drewbert60]

I have a 240V Hi-Leg Delta (B-phase) panel to feed a new 4-wire 240V 1ph Range receptacle. Since B-phase is 208-Neutral, do I risk burning up the 120v controls? Any advice would be greatly appreciated.

 

[mpoulton]

I have a 240V Hi-Leg Delta (B-phase) panel to feed a new 4-wire 240V 1ph Range receptacle. Since B-phase is 208-Neutral, do I risk burning up the 120v controls? Any advice would be greatly appreciated.

My understanding is that 1ph loads should always skip the high leg and use only the other two (120-to-ground) legs. Most POCOs require this for high leg services to minimize the load on the high leg, I think. Also avoids the problem you are referring to. Because yes, you definitely risk blowing up the control circuits since you have no way of knowing which leg they are connected to.

 

[JFletcher]

I have a 240V Hi-Leg Delta (B-phase) panel to feed a new 4-wire 240V 1ph Range receptacle. Since B-phase is 208-Neutral, do I risk burning up the 120v controls? Any advice would be greatly appreciated.

Use a 2p breaker across AC phase. The two legs to the range must be 120V to N ea, and the only way that happens is with using A and C.

eta: any other wiring configuration will be dangerous and NEMA 14-50Rs are designed and expected to have 2h, n, g, with 120VAC on each hot, 208/240V between. There is no way to wire a high leg into such a receptacle (legally/NEC or mfg-wise)

 

[ggunn]

I have a 240V Hi-Leg Delta (B-phase) panel to feed a new 4-wire 240V 1ph Range receptacle. Since B-phase is 208-Neutral, do I risk burning up the 120v controls? Any advice would be greatly appreciated.

Your 4 wires should be A phase, C phase, Neutral, and Ground. The only loads that should get the B phase are three phase loads with no Neutral.

 

[Frank DuVal]

Just Do Not run the high leg to the receptacle box! Then all you have to worry about is not connecting a hot wire from the receptacle to the high leg phase at the breaker. Use two pole breaker only.

 

[chris kennedy]

you definitely risk blowing up the control circuits since you have no way of knowing which leg they are connected to.

Wiring diagram.

 

[gar]

170105-2025 EST

If this is a residential application where most of the loads are single phase why would you not have a single phase main panel, and a separate 3 phase panel for the three phase loads?

If it is commercial or industrial, then two appropriately sized panels still might be a good choice.

The use of a two panel approach can avoid future problems, especially where electricians may not be familiar with high-leg sources.

.

 

[MiElectrician]

Nevermind