novemberaudi
Member
- Location
- boston
I have a job where i have to pipe for various low voltage alarm cables. Just looking for a little advice do I just figure the area of the cables and use 40% conduit fill or is there a better way.
low voltage conduit fill
- Thread starter novemberaudi
- Start date
- Status
Gregg Harris
Senior Member
- Location
- Virginia
- Occupation
- Electrical,HVAC, Technical Trainer
40% for over 2 conductors
- Location
- New Jersey
- Occupation
- Journeyman Electrician
What NEC Article do your cables fall under?
- Location
- Illinois
- Occupation
- retired electrician
In many cases, the NEC does not have rules covering conduit fill for low voltage cables. Many cable manufacturers have instructions that show wire fills of less than 40% and in one case that I know of limits the length of the pull to 100' of straight conduit, deduct 30' for each 90? bend.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
So if you design for the NEC maximum of 360 degrees, you can run -20 feet!
Sounds like their wire is pretty weak mechanically. That can happen with small conductors.
- Location
- Illinois
- Occupation
- retired electrician
I think it is a "CYA" thing on the part of the manufacturer. Like a lot of installers, we ignored the instructions, and made much longer pulls than specified on the supplied information sheet. We did not experience any cable damage issues.
The same time of issue exists in the BICSI standards. As I recall, their standard for the installation of "CAT" rated cable is the maximum pulling force is 25 pounds and this applies no matter how many cables are being installed.
- Status