Quote Originally Posted by Davek0974 View Post
Thanks, so there is no difference in current draw if a 3ph motor is running on 3ph or on converted single to 3ph via a vfd (apart from the internal vfd usage) ??
That depends on where you're measuring the current, which is why you use the KW rating to work it out.
I was going to mention just how much the VFD will allow the motor to run above it's rated power, but I see the supplier has answered that.
Although the motor is rated at 3HP/2.2Kw, that'll be at 50Hz speed rating. When you increase speed, you can think of AC induction motors just like a steppers, in that the key factor is how much current you're putting through the windings.
So double the speed, and you can double the power, which means your 2.2kw motor running at double the 50Hz speed could produce well over 4kw.
Off course as with steppers, you need to monitor temperature, and if running at low speed a lot, you may want to consider getting a forced induction kit for the motor (aka a cooling fan that bolts onto the motor) to avoid overheating the motor.