FLC for 800 Hp 460VAC Motor

[Sahib]

Not for me nor for most Brits. In fact we use kW, not HP anyway. It's one step fewer in the calculation............

You and me use only motor name plate current to size motor supply conductors. But in North America, the code has motor full load current table for motor up to 500 hp to do that. That is the distinction.

 

[Jraef]

I think that's a reply to Sahib's comment. ...

Yes, it was.

 

[Sahib]

The point is neither 1.2A/HP thumb rule nor motor full load current calculation has a basis in the code as does the motor name plate full load current.

 

[Besoeker]

You and me use only motor name plate current to size motor supply conductors. But in North America, the code has motor full load current table for motor up to 500 hp to do that. That is the distinction.

I'm aware of that.
But thread is about the current rating for an 800 HP motor which is outside the current rating table other than, as Jraef has pointed out, that general 1.2A/HP factor.

 

[Sahib]

I'm aware of that.
But thread is about the current rating for an 800 HP motor which is outside the current rating table other than, as Jraef has pointed out, that general 1.2A/HP factor.

See post23.

 

[Besoeker]

See post23.

This ship has sailed.

 

[don_resqcapt19]

Yes. NEC assigns motor full load current FLC which may not be same as motor name plate current FLA.

There is nothing in the NEC to support the idea that FLC and FLA are not the same thing. There is plenty to support the idea that you use the Table FLC for sizing conductors and overcurrent protection and you use the nameplate FLC for sizing the overload protection. The term "full load amperes" is not even used in Article 430. That article only uses the term full-load current.

 

[Besoeker]

There is nothing in the NEC to support the idea that FLC and FLA are not the same thing. There is plenty to support the idea that you use the Table FLC for sizing conductors and overcurrent protection and you use the nameplate FLC for sizing the overload protection. The term "full load amperes" is not even used in Article 430. That article only uses the term full-load current.

The voice of reason..........