That would be rule# 28.500,(3),(d)
You may suggest to the inspector that each motor is independently controlled by the motor protectors suggested by jraef and that the VFD is a separately derived source supplying a special power to the motor controllers.
Showing a printout of the drawing linked by jraef may help.
Alternately you may be able to obtain a declaration from the VFD supplier stating that the drive is suitable for supplying multiple, independently protected motors.
By the way, that rule has been added since I was designing systems with multiple motors on one starter.
We used a chart showing the ratio of starting current to running current for various sized motors. The ratio decreased as the motor size increased. Hence, ten one HP motors would have a higher starting current than one ten HP motor.
That may be part of the reason for the code change.
Another reason may be that control equipment manufacturers are heavily represented on the code committees.
Here is a
Link to the document containing the page extracted by jraef.
Note: This does not address the issues brought up by Skogs.
Bill
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"Why not the best?"
Jimmy Carter