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Running a DOL starter from a VFD 1

Greymoonstar

Marine/Ocean
Jan 30, 2025
4
I am trying to run a DOL starter for a Marine Hydraulic Power Unit.
The Starter runs a 220V 3-phase 60hz 2.2kW motor.
I am in the UK and my Factory supplies are 230VAC Single Phase and 415V 3-phase.
I have tried running a VFD as the supply to the starter, but when I engage to motor contactor in the starter, the VFD triggers a constant speed overcurrent error and cuts the supply.

The starter will not allow the motor contactor to engage without 3-phase, but if the vfd is running before I start the motor, it errors and cuts the supply.

Any ideas?

(First time poster)
 
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Or… use a VFD that is about 3x larger than the motor (using CT /HD sizing). Most drive transistors on CT/HD sized drives can handle around 200% current for 2 seconds. So given that the starting current of the motor will be roughly 6x, tripling the size of the VFD should get you there. Personally I would go next size up to be safe though.
 

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