VFD Wire Size for surface grinder

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Pevehouse

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Hello all, was just thinking and trying to plan out my wiring for the vfd install on my harig 618. Problem is I’m not sure exactly what size conductor to run to and from the vfd. It’s a pretty simple set up, a 2 hp three phase motor. Will be running 220 single into feed the vfd. I appreciate any input or comments on the subject, thanks
 
you could get away with 14g, but I would go 12, as you don't spend that much more, and benefit a fudge factor.
btw, all of this is on the net.. calculators to convert hp / volts to wattage, wattage to awg.
 
Ok, I will do a some digging for a calculator. I appreciate your input though. I already have plenty of cable in various sizes so I should be set. Thanks
 
NEC 430.122 dictates that for feeding a VFD, the line side conductors must be sized for at least 125% of the VFD rated input current rating (2 or 3 Hp is typically 20A/14AWG or 30A/10AWG breaker, wiring is specific to the breaker). It is not a factor of what the VFD is driving, the output (motor) wire is at least 125% of the motor FLA (assuming shorter cables), but would normally be 14-16 AWG for 2Hp @230V 3 phase. Also depends if the VFD power cable is a plug or hardwired. The input power wire size that may be used is a function of the breaker as well as the type of load. VFD manufactures will give recommendations as to breaker/fuse sizing as well as motor gauge in the manual. Typically a single phase 20A breaker for a 2Hp (230V) VFD is sufficient, in particular for a surface grinder which is a light load. The VFD output needs to be directly connected to the surface grinder motor and not used as a general machine power source.
 
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