load calculation & VFD with unknown motor load

[tortuga]

Greetings group I am doing a 220.40 feeder load calculation and all that is known about one of the loads is the input VA of a Variable Frequency Drive (VFD) and the pump its connected to is yet to be determined. Its a pretty large load so I tried to pin it down without success.
430.122 says to size the branch circuit and feeder conductors to an Adjustable speed Drive at 125% of the input current and I guess that's simple enough, so I don't need to know anything about the pump?
I realize 220.50 points to 430.24 430.25 and 430.26 not 430.122, however since the drive is the 'load' is it incorrect to ignore 220.50 and go with 430.122?
The drive in question is for a pump that takes a single phase input and has a 3 phase output like this one
I suppose even if the pump was known, then the calculated load may not be reduced below 125% of the drive input VA either way?
Thanks in advance

 

[don_resqcapt19]

The rule only applies to the conductors and not to the branch circuit rating or its OCPD. It would be a worst case for load calculations. The drive is a controller and is not a load. The motor is the load.

If the motor is smaller than the maximum size the drive can support, there may be information in the drive manual that would let you reduce the input conductor size.

Remember when using the drive as a phase converter the input current will be approximately twice the motor current.

 

[tortuga]

The rule only applies to the conductors and not to the branch circuit rating or its OCPD. It would be a worst case for load calculations. The drive is a controller and is not a load. The motor is the load.

If the motor is smaller than the maximum size the drive can support, there may be information in the drive manual that would let you reduce the input conductor size.

Remember when using the drive as a phase converter the input current will be approximately twice the motor current.

Thanks Don good info.