conduit fill

[lavelle]

how do calculate conduit fill when using category 5 communication cable?

 

[earlydean]

Re: conduit fill

Look on page 617 of your 2002 NEC, Chapter 9 Tables. Read all the text, but pay particular attention to note 9. You need to measure the cables, then do the math, or compare them to trade size wires with the same diameter and go with the charts.

 

[don_resqcapt19]

Re: conduit fill

Note that some of the communications cable manufacturer's recommond a maximum wire fill of 25%, not the 40% permitted by the code. The also often recommend only 270? of bend between pull points. This is because excessive pulling force will damage these cables. The folowing is from Belden.

Installation Suggestions
This chart is based on the maximum number of cables permitted in conduit under the National Electric Code, and is calculated on the area of the cables with 40% of the conduit filled. *For conduit runs of 50 to 100 feet, the installed number should be reduced by 15%, or use the next size larger conduit. Each 90? conduit bend may be estimated as equal to the friction of 30 feet of straight level conduit. If more than two 90? bends are to be used in the conduit run, or if the run is to be over 100 feet in length, insert a pull box. The use of anti-friction agents is recommended during pulling operations.
Caution: Be sure the anti-friction agent selected is compatible with the cable jacket material. (Check the label.)

Don

 

[tom baker]

Re: conduit fill

BISCI (the telcom folks) recommends no more than 25 lbs pulling tension on cat 5, 5e or 6 cable. get some 25 lb fishing line and tie it to the end of your fish tape.
check out the BISCI web site for more than you want to know on telecom standards, installation, certification and so on.