Multiple Motors From Same VFD
Multiple Motors From Same VFD
(OP)
I hava an application where I have 6 motors that will never be required to run at the same time. I would like to use just 1 VFD to save $$$. Can I use one motor starter and some downstream contactors to pull this off, and is there any code issues I should worry about. I am a ChE and have some knowledge of industrial control, but I am not an EE or electrician.





RE: Multiple Motors From Same VFD
RE: Multiple Motors From Same VFD
However, unless you are talking about large motors, you may find that it would have been cheaper to buy individual drives. Operations and maintenance is much simpler with individual drives as well.
RE: Multiple Motors From Same VFD
how about the issue of all 6 motors cannot run because of the lone VFD failure?..unless of course you have a spare you can pull out quickly..
dydt
RE: Multiple Motors From Same VFD
RE: Multiple Motors From Same VFD
RE: Multiple Motors From Same VFD
Damage can occur to the motor if the running watts exceed the name plate rating of the drive.
Similarly each drive has built in thermal protection. You must check the current you draw from the drive against its name plate rating.
As long as you remain in the limits, thru an electrical interlock, every thing will be OK.
RE: Multiple Motors From Same VFD
RE: Multiple Motors From Same VFD
That which does not kill me, makes me stronger... and pissed off!
RE: Multiple Motors From Same VFD
Additionally, it seems like horsepower-rated contactor switching may be equally or more expensive compared to dedicated VF controllers. Typically each motor would use two 3-pole, electrically and mechanically interlocked contactors. It is possible unit pricing on a quantity of VFDs may be significantly less than the single-lot price.
RE: Multiple Motors From Same VFD
RE: Multiple Motors From Same VFD
RE: Multiple Motors From Same VFD
RE: Multiple Motors From Same VFD