Will I be able to run 100 RG-59 cables in a 4" conduit? If not what size conduit will I need?

Answer 1

My guess is no without doing the math or research.

Check out the National Electrical Code (NEC) it will tell you about how full a conduit can be.

The other thing is that you have to pull all those wires through and the fuller the conduit is the harder it is to pull wires through.

Answer 2

Why not try another type of enclosure. Check out "boxway". Ref. Square D on-line for a look at it. Nice thing is that you don't have to "pull" stuff through it. And, if you need more later, it is easy to add. Meets code (coax should be Class 2 anyway, so the code is pretty lax there.)

Another thing about coax -- if you pull it you run the risk that you will have some places where the coax stretches a little and reduces its diameter. That will cause a local change in the impedance of the coax and associated signal reflections. If I'm guessing right and RG-59 means video signals, they you will have ghosting.

Answer 3

I did a little quick figuring, and yes you should have room to spare.