Which is more common - split phase or 3 phase wye?

[MarkGallimore]

In an industrial laboratory environment - (metalurgical / chemical lab) - which is likely to be more available a) split phase wiring which would allow me to get a 240v supply from the two hot legs b) 3 phase wye wiring which would allow me to get a 208v supply or c) both are usually available in the same lab. I've a heater in some equipment which is borderline in capacity and the prospect of only having 208v available might mean I can't get sufficient heat from my equipment.

Cheers

Mark

 

[dpc]

That's really going to be location specific. If this lab is within a large industrial facility, then 208/120 three-phase will be much more common. If it is in a strip mall, then probably 120/240 single phase will be provided. When designing industrial facilities I usually try to avoid any 120/240 V panels.

For specific equipment not available in the voltage that you have, a buck/boost autotransformer can be used to obtain the desired voltage. Changing from 208 V to 240 V or vice versa doesn't take much of an autotransformer since the voltage difference is so small.

 

[jraef]

I agree. If you are specifying a power source for your equipment and if 208V may not work, then simply specify that criteria. Provide or require a boost transformer to supply the voltage you really need rather than try to 2nd guess what the user may have. It's pointless because they have what they have.

By the way, in answer to c), there is rarely if ever a dual service in a facility.