I am running cat6 cable at a job. I was wondering if anyone knows how many calbes can be put into a 3/4", 1", and 4" pvc conduit that the electrician is piping in for me. Heading into my closet I will have about 160 cables. He is proposing 2-4" conduits. Will that be enough?

p.s. Where can I find documentation on this?

Thanks,

Doubled

I've got 98 cat5 cables split between 2 1.5" conduits, so 2 4" should handle it with room to spare. The only thing I know would be to start shoving cable into a piece of conduit and see how many will fit.

The National Electric Code book is where you would find that info. An inspector once told me not more than half full, but would allow 3/4.

Thanks for the help guys. I know the code book says that you can only fill a conduit 60% full (MN), but I found out that the inspector doesn't worry so much about that as to making sure all of my cables are tied up by their own supports.

How long are the conduits? If only going through a wall, you can fill them completely. Going very far, use 50-60% fill maximum or it will be really hard to pull and you could damage the cables. If I remember, the codebook says 50% fill to limit heat buildup from current-carrying wires.

Also dn't forget to allow for any future runs
and no more then 3 90s per run.
Add any 45s or kicks also.
It's a real PITA to get 80 or 100ft of cable into a pipe only to find the EC didn't use a bender or install the couplings properly.
You'll find yourself breaking the pipe in the middle of the run.

You're all right ---- maybe. TIA 568 and the NEC give the support and fill rates. The average (depending on the size of the wire) into the face surface is the figure. Even though the NEC calls for current load bearing conductors the TIA 568 follows the same as electrical.

The average cable count per sq inch surface face for General Cable is 28. At 55% fill on a 4" you should get just over 160 per pipe. Get the wire specs from your vendor,
figure your sq inches of pipe face ( size X 3.14) divide by fill rate (schedule by pipe size in NEC/ TIA) times the size/number of wires in one sq inch. Confusing? Oh Yeah !! Had to do it on a hospital job in Pennsylvania to make the state inspector happy. He was a rough dog to convince. He also wanted to pull our face plates to check for fire stop --- didn't want to be charged for re-certifaction.

Sorry to be long winded but the inspector is ALWAYS right.

Explain a little more on the fire stops behind the faceplates. Aren't the faceplates themselves fire-rated? Are you talking about around the actual box?

Don't you hate it that the inspector is always right, even when they are dead wrong?

5 Year, oh are you so right.

The fire stop issue was the box was cut into the fire wall between the patient room and the hall way. Metallic flexible conduit was run inside the wall and out into the hallway ceiling. This penetration of the fire envelope required the flex to be firestopped where it entered the box in the room and a knot of fire stop at the top of the flex where it entered the cable tray thus sealing the pathway.

I thought the city inspector in Philly was rough ---- you should have seen the State Fire Marshall inspection !!!!
The inspector had one eyebrow ----- over one eye, one broken fang, and raw knuckles from dragging on the sidewalk ---- he was a REAL pain. He got whatever he wanted !!!!

Now in Wisconsin, in certain applications including hospitals, you have to pack the backsides of the boxes in 2 hour rated firewalls even if you do not penetrate to another space. What a pain.