I have a 10hp 3 phase motor that I'm driving with a 20hp VFD using plain ol' single phase 240 volt. The VFD manual states that the VFD can be used with single or 3 phase input.
The manual specs 4 awg wire from the panel to the VFD. The manual also specs a 65 amp magnetic contactor between the panel and the VFD.
Is a 65 amp magnetic contactor robust enough if I'm supplying the VFD with single phase and not 3 phase? I was thinking an 85 amp contactor would be more in line if using single phase to power the VFD, which would also match the ampacity of the 4 awg wire.
For reference the 10hp motor is on an air compressor, running at 208 volts. The motor tends to draw roughly 30 amps, and the VFD draws about 45-55 amps (depending on the air pressure), but can spike to 70 amps when the motor is just starting.
Thanks for the help.
The manual specs 4 awg wire from the panel to the VFD. The manual also specs a 65 amp magnetic contactor between the panel and the VFD.
Is a 65 amp magnetic contactor robust enough if I'm supplying the VFD with single phase and not 3 phase? I was thinking an 85 amp contactor would be more in line if using single phase to power the VFD, which would also match the ampacity of the 4 awg wire.
For reference the 10hp motor is on an air compressor, running at 208 volts. The motor tends to draw roughly 30 amps, and the VFD draws about 45-55 amps (depending on the air pressure), but can spike to 70 amps when the motor is just starting.
Thanks for the help.