Sizing of coiled cable

[lilsparky]

Hi all,
I would like to use coil cable to 3 different motors moving in different axes. I have never used coiled cable and was wondering do I size them the same way I size any cable to motors. I have 3 single phase motors and one 3 phase 10 hp motor.

Thanks!

 

[jcormack]

derate

derate

Cable on a cable reel has to be derated because of the heat build-up caused by mutiple laps of current carring conductors.

 

[lilsparky]

Is this specfied in the NEC code?

 

[broadgage]

May not be in the NEC since it could be considered as an appliance and not part of the installation.

If cables are wound on a drum or reel, then they need de-rating, often substantialy.
A number of manufacturers offer self retracting cable reels for moving loads, they should be able to advise on the safe current.

If on the other hand we are talking about flexible cords that are self coiling/extendable and not wound on a drum or reel, then normally no de-rating is required. #12 coiled or curly cord would have a similar ampacity to regular cord, unless the supplier directs otherwise.

 

[Jraef]

May not be in the NEC since it could be considered as an appliance and not part of the installation.

If cables are wound on a drum or reel, then they need de-rating, often substantialy.
A number of manufacturers offer self retracting cable reels for moving loads, they should be able to advise on the safe current.

If on the other hand we are talking about flexible cords that are self coiling/extendable and not wound on a drum or reel, then normally no de-rating is required. #12 coiled or curly cord would have a similar ampacity to regular cord, unless the supplier directs otherwise.

I agree, you need to clarify if you mean a curly cable, i.e. coiled like a spring, or wound on a payout reel. If it's on a reel, there are derating factors to apply based on the depth of the reel, meaning the number of coils or laps on top of each other.

http://www.cdc.gov/niosh/mining/topics/electrical/deratingfactors.htm