Cable and electric burial question`

[cruzin]

Hi, digging a trench to put a 1 1/4 grey pvc tube in for my coax (cband flat ribbon and 5 RG6) 70ft from the house.
I would like to have electricity out there also. I was told by a salesman at HomeDepot not to run the 120ac line with my coax. He suggested a seperate plastic grey tube would be ok. If I run the 120ac in the same trench in a seperate or the same 1 1/4 tube will it cause me signal problems?

 

[brentb636]

You won't have a problem unless you plan on running some high current device on your 120 VAC line. The issue is one of induced voltage into your flat ribbon cable. The induced voltage is proportional to the current in the 120VAC line. Your coax is shielded and I doubt even running a welder out there would affect the signal itself. If you're just going to run a reciever and TV set, I wouldn't be concerned .

 

[cruzin]

You won't have a problem unless you plan on running some high current device on your 120 VAC line. The issue is one of induced voltage into your flat ribbon cable. The induced voltage is proportional to the current in the 120VAC line. Your coax is shielded and I doubt even running a welder out there would affect the signal itself. If you're just going to run a reciever and TV set, I wouldn't be concerned .

I was wanting it out there for just that having a tv and receiver out there for tunning purpose. And I thought I may need some powered switches. So you do not think running the satellite and the ac in the same pipe or different pipes in the same trench? thanks for input.

 

[brentb636]

IF you were going to use separate conduits, One of them should probably be RIGID conduit for the shielding and isolation that it provides. That would be expensive. I would put all the conductors in the same conduit, and if there appeared to be interference, I'd have a disconnect for the 120 VAC circuit, when it wasn't in use.
I'm not a expert on this, but I am a retired electrician with a lot of communications experience.

 

[guapoharry]

For whatever it's worth, the telephone guy told me they do common trench with the electric utility.

To make it safe and to code, doesn't that need a GFCI and the new exterior outlet housing? I defer to the electrician on this...

I agree the coax should be fine. I don't know if the ribbon cable would have an issue.

If you won't be using the AC frequently, why not use an extension cord instead?

Powered switches use a transformer. That would require a weather-proof enclosure that keeps the unit within its temperature limitations.

 

[cruzin]

Thanks for all the input, I can just shut the breaker off when not in use. I may need powered switches some day down the road. thanks again.

For whatever it's worth, the telephone guy told me they do common trench with the electric utility.

To make it safe and to code, doesn't that need a GFCI and the new exterior outlet housing?

I agree the coax should be fine. I don't know if the ribbon cable would have an issue.

If you won't be using the AC frequently, why not use an extension cord instead?

 

[brentb636]

For whatever it's worth, the telephone guy told me they do common trench with the electric utility.

To make it safe and to code, doesn't that need a GFCI and the new exterior outlet housing? I defer to the electrician on this...

I agree the coax should be fine. I don't know if the ribbon cable would have an issue.

If you won't be using the AC frequently, why not use an extension cord instead?

Powered switches use a transformer. That would require a weather-proof enclosure that keeps the unit within its temperature limitations.

Code requires GFCI protection on the 120 VAC circuit. Easy to do and not expensive. I'd source the feed from a new GFCI receptacle and use the receptacle "TEST" button as the disconnect means. About a $7.00 solution .

 

[Cadsulfide]

I'm pretty sure code forbids communication and line voltage wires to co-exist in the same pipe. I would not worry about coupling/ interference problems at 60hz.

UF (grey jacket) direct burial rated romex cable is excellent for your application, run it alongside of the pvc. Or if you prefer (me too), lay another run of pipe in the trench, 3/4" should work fine for 14/2. If you run a 2nd pipe, you wont need UF wire.

As for the GFCI, put it indoors and run your feed off the protected side of the unit, far fewer false trips, and as Brentb636 said an easy "off" switch.

 

[pedrogarcia]

Cruzin > Just a thought if you have not already bought the tube increase the size. 1 1/4 may seem large enough but the larger the better in case you have to pull through a replacement or additional cables. The extra cost is not that much compared to the sweat later especially if you have a couple of pipe bends. If you are near Kzoo I have 100 ' 3/4 Carlon flex plus blue tube you can have for your 120v (free).

 

[cruzin]

Cruzin > Just a thought if you have not already bought the tube increase the size. 1 1/4 may seem large enough but the larger the better in case you have to pull through a replacement or additional cables. The extra cost is not that much compared to the sweat later especially if you have a couple of pipe bends. If you are near Kzoo I have 100 ' 3/4 Carlon flex plus blue tube you can have for your 120v (free).

Hey thanks for the offer. I work down there on occasion but not in the near future. I have another 3/4 pipe I think I will run the 110 line in. thanks again.