Bought a MEP Cobra 350 cold saw and it runs on 480 3 phase. Only have 240 single phase and already run plenty of machines with VFD's converting to 240V 3 phase.
So with this project, the motor needs 2200 watts @ 480 3 phase.
Bought a 480 to 208 transformer that is configurable as buck/ boost. Rated for 3KW. Wired the 208 side to a 5HP VFD feeding it from the 240 single phase.
Used the lowest voltage windings on the 480 side ( think they are 432) , by calculations this should give 499V to the motor.
Well it works. Motor powers up fine via the VFD start/stop. Currently using a 5 second dwell up and down.
Here is the question. The VFD says the output current is 11-12 amps for about 10-15 seconds of on time. After that the current goes up to about 20 amps. Whats up? It all runs flawlessly.

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