VFD 440V & variable suppy in same cable?

[roys]

Was discussing various options for some modifications that may be coming up, and one of the options doesn't sound great but I can't quite put my finger on why not.

So 440V 3 Phase supply going to VFD from a DOL starter. After VFD out to motor (which sits close by location of DOL starter), due to the locations of VFD and DOL starter the two sets of 3 phases (DOL and VFD) could be ran in the same 7 core SWA cable saving a double cable run. Motor approx 3 HP.

I don't like the sound of this option, but not sure why exactly, thinking of harmonics, and also to me it is not quite as neat due to this method would require a marshalling box to split out the supply once it comes back from the VFD if you know what I mean. I would prefer just to put the 3 phase from DOL to VFD in one SWA cable and VFD to motor in another. Just not sure how to say that I think my way is better.

Any thoughts, sorry for the description not being as clear as I would have liked but it is kind of hard to describe. Cheers folks.

 

[Technician]

What is VFD?

Is it variable frequency drive?

 

[roys]

Yes VFD = Variable Frequency Drive.

 

[roys]

Thanks Canoeboy, thought you would be the first to come up with an answer . We don't have any manufacturers data just now only at the mulling over stage which is why I thought I would bounce it about this forum.

Thanks again.