Industrial service drops and FMC

jbornswede

Member
Location
Thompsons Station, TN
Occupation
Engineer
I've spent some time looking, and can't seem to find the answer...hoping somebody has a lead. I understand we are not permitted to use flexible cabling in the place of permanent wiring. We have multiple power drops in our facility that probably should be installed in conduit. Can we use FMC instead of rigid conduit? There is really no place along the drop to support the FMC...is this allowed?
 

jbornswede

Member
Location
Thompsons Station, TN
Occupation
Engineer
Permanently installed Pendant drops are one of the few permanent uses of SO cord. Most likely legal as is
Thank you letgomywago! However, we are not using them as pendants (i.e., there's not a free hanging outlet at the end), but either hardwired into a machine or hardwired into a series of outlet boxes installed permanently on workbenches...does that change your opinion?
 

MTW

Senior Member
Location
SE Michigan
I've spent some time looking, and can't seem to find the answer...hoping somebody has a lead. I understand we are not permitted to use flexible cabling in the place of permanent wiring. We have multiple power drops in our facility that probably should be installed in conduit. Can we use FMC instead of rigid conduit? There is really no place along the drop to support the FMC...is this allowed?
I have always used bus drop cable, with the proper spring strain relief hanger hardware. it's called out in the NEC busway article for use only for bus drops. But I have used it for many years in plants. Have never had an inspector complaint when done the proper way with the right hardware. Box at the top of the drop supplied by pipe. with a ceiling mounted box. strain relief mesh grip chord connector installed in the box cover.
short drop loop out of the box cover over to a truss mounted sky ty spring support hanger A loop of extra cable around the sky ty hanger for flexibility,, minor repositioning ability, and strain relief take up then drop down to the machine mounted box, normally with a disconnect. Strain relief mesh chord grip at the bottom.






Some picture examples in this thread.
 
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