VFD Cable For Motors Below 10 HP

Should i run vfd cable for motors smaller than 3 hp with runs no mor than 100 ft.

I have been told that motors less than 100 ft. (actually 150 ft.) of wire length from the drive do not need the special cables
or output reactors, but I have also seen motors lose bearings due to VFDs when the wire length was less than 100 feet.

If it can afford it, I usually use the VFD cables/ reactors.

I'm no expert on this, but I would think the anticipated speed range might play into this, too. If you only run close to the motor's base speed, wouldn't standard cables be just fine, regardless of the distance?

Steve

Yea, it is somewhat depenant on Freq. and application But remember the VFD even running at 60hz is still producing harmonics that you would not have otherwise. So IMO unless it is cost preventive go with good VFD cables. It may prevent problems later and it's easiest to do on the front end rather than later.

PLC, after all that's been said on this subject lately, I'm a little surprised at your question.

But, to repeat, the answer is "it depends".

First, is there sensitive equipment close by that needs the protection of VFD cable?

Second, is the voltage 600, 480, 230, or 208? The higher voltages are more likely to need the suppression than the lower.

Third, is the motor an MG1P31 motor? Lower spec motors can sometimes be made to survive on VFD's with VFD cable and/or reactors/filters.

Fourth, are the motor leads in metal conduit, plastic conduit, or open trays?

See what I mean? Each of these has been discussed before, often with your participation in the thread. I don't mean to be a jerk here but consider this to be just a gentle nudge to do a little research before asking. OK?