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Flexible cable carrier

Flexible cable carrier

Flexible cable carrier

(OP)
Does anybody know how a flexible cable carrier (like
cat-track) is treated by electrical codes? A facility
inspector states that this carrier (attached to AC motor
frame) must be considered as a cable tray, and only
cable tray rated conductors can be used. Is he right?

RE: Flexible cable carrier

Flexing duty seems like it would be a greater concern.

Assuming a 600V system, search on: Type-NVN or –SDN (Flexing-duty pendant cable on a “shower” rod assembly [festoon] might work.)  Stay away from SO cord for this application—it does not hold up very well with other than minor flexing.  Heating occurs where cable jacket and wire insulation meet and strand breakage results—usually when the equipment if most needed.  

http://www.iewc.com/catalog/HiFlex20Scope.htm

http://www.cliffordvt.com/traycable_text.html
SDN Flexible Control Cable, 600 Volts, UL Type TC Tray Cable, 90°C
Polymer/Nylon Insulation, Neoprene Outer Jacket
Especially suitable for flexible applications such as festoon installations on cranes re-reeling and unreeling installations, at temperatures down to -55°C.

RE: Flexible cable carrier

(OP)
Thank you, busbar. But I am not looking for flexible tray
rated cable (at least, for now). The question is whether
this flexible cable carrier is correctly qualified as a
cable tray.

RE: Flexible cable carrier

Sorry--I got in a hurry reading your original post.  

I'm not sure I exactly follow your request.  I don't visualize plain-vanilla tray as anything other that a rigid means of support, except maybe at expansion joints.  Would it be possible to request some references to support the client's/specifier's/inspector's(?) frame of reference?  

Could you elaborate on the benefit to classifying the 'carrier' a cable tray?  

RE: Flexible cable carrier

If your flexible cable carrier is as I suspect, and as Busbar was thinking, is such as Gleason PowerTrak, than it requires flexible cable.  We have some powertrak installed, and it is all treated as portable power equipement, whether the cord drags on the ground, or moves in the track.

Probably at issue here is the flame test rating of the cable, this is some times a function of local fire codes besides electrical codes.

Gleason supplies, and we also use type SO and type W cable in our installations, and the only problem we usually have is when it gets burned of by slag and hot metal.  The power track limits bending radius to two feet in our case, but if a small bending radius is required Busbar's suggestion is likely vital.

Gleason doesn't have much useful info on their site, but feel free to dig a little deeper.

www.hubbell-gleason.com

RE: Flexible cable carrier

(OP)
Some details to my original question. We have a translating
frame dynamometer (AC motor fed from PWM drive) built in
Germany and supplied with special VFD rated flexible shielded 3 phase cables with 3 symmetrical ground
conductors. The usage of this cable is a must per vendor spec. This cable IS NOT tray rated. We run these cables
from converter to motor frame in rigid metal conduit. At the frame the conduit exits the cable trench. From this
point cable enters a cable carrier (similar to Gleason) and
goes to the motor J-box. Do we have any grounds to state
that this flexible cable carrier SHOULD NOT be classified
as a cable tray and NOT TRAY RATED cable can be used?

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