Underground Cabling

[FarmerCharlie 0]

I am running water and electricity a couple hundred feet from the house. I thought I would go ahead and add CCTV cable in the same trench, and I'm not sure what to use. The only rated underground I can find is RG6 at about $.10 per foot with a flooded polyethylene jacket. My cameras are all analog. Is this the cable I should use? Or is there a suitable Siamese cable for power and audio?

[thewireguys 3]

I would recommend you install conduit and then you can decide what cables you want to use later. Also the wires will be protected and you can upgrade down the line.

[FarmerCharlie 0]

I would recommend you install conduit and then you can decide what cables you want to use later. Also the wires will be protected and you can upgrade down the line.

I had not thought of that. The water line I am using is 3/4 inch flexible polyethylene line. Would it work if I just add a second one to use as a conduit? If so, should I install a pull wire when I bury it?

[hardwired 0]

That should work, as long as you keep a reasonable radius in any turns or sweeps. You will not be able to fit very many RG6's in that, though.

 

You may want to pull direct burial CAT5 cable, then you could run up to four analog cameras per cable with baluns, or go network based through it.

 

Try to keep a reasonable amount of separation between the high voltage conduit and the low voltage stuff to avoid interference, for instance bury the high voltage at 18-24 inches, and the low voltage at 12 or so (check your local codes)

[FarmerCharlie 0]

Thanks for the quick replies. This has got me going in a whole new direction. Maybe I'll use some 1 inch tubing. Would I be able to push a solid pull-wire 200 feet later? My snake is not that long.

[thewireguys 3]

Put a good pull string in it

[survtech 0]

The way to do that is with a shop vac and a pull string attached to a foam ball or a "conduit piston". essentially, you attach the vacuum to one end of the conduit and pull the string through with it. Make sure the conduit piston is just slightly smaller than the conduit.

[hardwired 0]

Pushing would be difficult, at best. Look for a tool like Survtech mentioned.

 

Or, if you're cheap (like me) you can try using a small corner of a plastic bag, tied to kite string, to do the same thing.

[tweak'e 0]

do not put video cables in the trench with power cables. very easy to get interference and its a pain to fix later.

a bit of flexy water pipe is ok to put them in but i prefer hard pipe (ie electrical conduit) so the ground doesn't squish the pipes.

 

if the pipes are fairly straight just bury it with a few pull cords in it to drag cables through. tho a couple hundred feet i would put cables through before burying them.

also check how the pipes come out of the ground, you want them to breath so any water can evaporate out of them. otherwise they can fill up with water and they can do weird things,especially any type of twisted pair cable.

[tomcctv 190]

Put a good pull string in it

and every toolbox should have a good tool to pull it. and with so much gear on the market i have found this to be the best. http://www.youtube.com/watch?v=BCgUgnGrHAs

[FarmerCharlie 0]

I decided to use 1" plastic conduit. It is in 10' sections, so I can use a snake to pull the strings through as I assemble it.

 

I figured I would cover the water and electrical lines with about 1 foot of dirt and then add the conduit for the video cable. Does that sound like a reasonable compromise?

 

Thanks for all the suggestions.

 

Charles

[tweak'e 0]

1 foot is fairly minimal. will depend a lot on how much power is going through the power cables.

[Soundy 1]

The way to do that is with a shop vac and a pull string attached to a foam ball or a "conduit piston". essentially, you attach the vacuum to one end of the conduit and pull the string through with it. Make sure the conduit piston is just slightly smaller than the conduit.

 

This is the easiest, by far. Don't need anything fancy on the end of the string, we just use a piece of a plastic bag.

 

Feeding the string through each section of pipe as you assemble it is going to be a real pain, with 20 or so sections, and if you're gluing the sections together (as you should), there's a chance of the string getting glued in place.

 

Assemble the pipe first, make sure to properly glue all the sections together, and then use a shop-vac as survtech suggests.

[FarmerCharlie 0]

[...]

Feeding the string through each section of pipe as you assemble it is going to be a real pain, with 20 or so sections, and if you're gluing the sections together (as you should), there's a chance of the string getting glued in place.

 

Assemble the pipe first, make sure to properly glue all the sections together, and then use a shop-vac as survtech suggests.

I think I'll follow your advice. Good thing I checked here before I started.

[FarmerCharlie 0]

1 foot is fairly minimal. will depend a lot on how much power is going through the power cables.

The electrical power is only for occasional use. Most of the time there will be no current, and I could even switch that leg off if it turns out to be a problem.

 

When I first dug the trench it was just for water and power. The camera idea came later. I would go back and dig it a little deeper, but the trencher has already been returned.

[FarmerCharlie 0]

What sort of marking tape can I get to put near the top of the trench? I would like it to be detectable with something simple (like a metal detector).

[hardwired 0]

Something like this should work.... http://www.grainger.com/Grainger/items/1N966?Pid=search it's stretchy, too, so if a backhoe or other equipment grabs it, you'll see it coming out of the hole. Like you mentioned, put it towards the top of the trench, so someone hits it before your cable.