Number of wires includes ground?

[cppoly]

Basic question here, does the number of wires listed in a product data sheet include ground?

A datasheet says the electric requirement is 220V - 3 wire but doesn't specify single or 3 phase. Single phase could be 2 hots + 1 ground to satisfy 3 wire. Or 3 phase could be 3 hots to satisfy 3 wire if the ground isn't included. Does the NEC have a standard on this?

Also, this equipment is for commercial buildings, so shouldn't the voltage be really specified at 208V? It's a violation to provide the wrong voltage for equipment. B/c after voltage drop the equipment might only see 200 V...

 

[don_resqcapt19]

In general, the EGC is not counted when you see a spec like that.

A grounded conductor would be counted, so that spec could be for a three phase system with three ungrounded conductors, or for a single phase system with two ungrounded conductors and a grounded conductor.

 

[realolman]

Basic question here, does the number of wires listed in a product data sheet include ground?

A datasheet says the electric requirement is 220V - 3 wire but doesn't specify single or 3 phase. Single phase could be 2 hots + 1 ground to satisfy 3 wire. Or 3 phase could be 3 hots to satisfy 3 wire if the ground isn't included. Does the NEC have a standard on this?

Also, this equipment is for commercial buildings, so shouldn't the voltage be really specified at 208V? It's a violation to provide the wrong voltage for equipment. B/c after voltage drop the equipment might only see 200 V...

That's a pretty crappy non-specific spec IMO... why would anybody even write a thing like that?

 

[Smart $]

I would typically assume a 3 wire requirement lacking any 3? indication to mean 1?.

 

[Smart $]

...

Also, this equipment is for commercial buildings, so shouldn't the voltage be really specified at 208V? It's a violation to provide the wrong voltage for equipment. B/c after voltage drop the equipment might only see 200 V...

Some manufacturers choose to indicate equipment that will operate on either 240V or 208V systems as 220V, as it is within +/-10% of both.

 

[cppoly]

Some manufacturers choose to indicate equipment that will operate on either 240V or 208V systems as 220V, as it is within +/-10% of both.

Yes, but if the system voltage is 208V then the 220V equipment could see 198V with a 5% voltage drop.

 

[Dennis Alwon]

If a neutral is required it would usually say 240/120.

 

[Smart $]

Yes, but if the system voltage is 208V then the 220V equipment could see 198V with a 5% voltage drop.

Yes, it could... and I understand your concerns... but only the manufacturer can address them.

 

[Smart $]

If a neutral is required it would usually say 240/120.

IMO, just the fact the datasheet states 220V supply indicates the manufacturer isn't using what we consider standard nomenclature.