Kayos
Gone......
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Generally, starting current could be up to 6 times running current - but only at the instant of initial starting (zero speed) when the motor is more of a resistive than an inductive load.
Applying Ohm’s Law to the windings might give the absolute maximum current draw.
However that surge will only be transient and VFDs will have a spec for transient overloads of both magnitude and time (before tripping).
The overload will not be for long - dependent on whether starting on or off load.
The VFD supplier should provide the requirement for your particular kit? Not us remote individuals without the experience and the finer details of the installation.
I was hoping the get a reasonable estimate as I want the DNO application in today, my quick calcs mean the £100k upgrade is needed.
I shall hold off until after the factory visit next week