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I haven't been following closely so sorry if I am out of line :
Using CTs on AC lines works great for motor amp readings........until they are placed downstream of a VFD.
The readings are based on peak amperage, sort of. A VFD sends full amps, but at a shorter duty cycle when running slower. We found the CTs would show near FLA when the motor was spinning at say 25%
Your control circuits and PWM may be different though.
In a VFD the only amp reading that is reliable is the one generated by the VFD itself. IDK is it is read from the DC bus or is an assumed value.
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