Trenching for power and data

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Hey all...thanks in advance!

I recently renovated a barn on my property into an apartment for my mother-in-law, who lost her home in a fire.

The barn runs on 100 amp service from my house...140 feet away, and is buried 6 inches deep, not in conduit. Sooo...in September, I will be trenching down 24 inches to run a new line, in PVC conduit.

While I am there, I want to add cable (RG6) and data (CAT 6) and possibly phone wires to the barn.

I "know" I shouldn't but data and power lines in the same conduit, but is there a minimum distance they should be separated by?
Can I just put 2 conduits on top of each other?
Is it OK to direct bury the RG6 and data on top of the conduit, assuming I use the correct wire?
 
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Unless required by a local ordnance there is no requirement for separation if they are in separated raceways. A lot of people reference 12” but that is from the utilities code and not applicable to your situation. With digital circuits in interference is not as big a deal in residential use. If some distance can be left 6” -12” it is a good piece of mind insurance.
 
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Hello - There a large number of electrical code that will have to be applied to your installation.

If you are using a conduit to span the distance between your main service panelboard to the separate location you must:
Set up a complete grounding system at the detached dwelling. It cannot be tied to the grounding system at your dwelling.

I will assume that you will be running individual wires through the conduit. If so the type wire you use must be listed for wet location. And since you are using Non Metallic conduit, the NEC requirement is 18" below grade. It is 24" if you are using direct bury cable. See 2017 NEC, Table 300.5.

You must bring at least 4 wires to the secondary panelboard. Black, White, Red and Green in order to provide for 240V devices. The cables have to be chosen from NEC 310.15 (B) (16)

It would also be wise to follow the NEC recommendations regarding "Voltage Drop" The NEC recommends basically that there be no more than a 5% drop in voltage end to end of the cable. This would mean that since you are going a distance of 300' you may have to use larger wires to handle the loss of voltage which will drive up your cost. Given the cost of Copper right now you may want to choose Aluminum for the feed to the mother-in-law home.

Your main service panelboard has to able to accommodate a 100 Amp breaker. You absolutely cannot take taps off of the incoming service lines to feed the secondary panelboard!

If you have more questions, just let me know.
 
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Do
Unless required by a local ordnance there is no requirement for separation if they are in separated raceways. A lot of people reference 12” but that is from the utilities code and not applicable to your situation. With digital circuits in interference is not as big a deal in residential use. If some distance can be left 6” -12” it is a good piece of mind insurance.
Should I put both wires in different conduits?
The data line, just CAT 6, will be direct burial grade
 
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Hello - There a large number of electrical code that will have to be applied to your installation.

If you are using a conduit to span the distance between your main service panelboard to the separate location you must:
Set up a complete grounding system at the detached dwelling. It cannot be tied to the grounding system at your dwelling.

I will assume that you will be running individual wires through the conduit. If so the type wire you use must be listed for wet location. And since you are using Non Metallic conduit, the NEC requirement is 18" below grade. It is 24" if you are using direct bury cable. See 2017 NEC, Table 300.5.

You must bring at least 4 wires to the secondary panelboard. Black, White, Red and Green in order to provide for 240V devices. The cables have to be chosen from NEC 310.15 (B) (16)

It would also be wise to follow the NEC recommendations regarding "Voltage Drop" The NEC recommends basically that there be no more than a 5% drop in voltage end to end of the cable. This would mean that since you are going a distance of 300' you may have to use larger wires to handle the loss of voltage which will drive up your cost. Given the cost of Copper right now you may want to choose Aluminum for the feed to the mother-in-law home.

Your main service panelboard has to able to accommodate a 100 Amp breaker. You absolutely cannot take taps off of the incoming service lines to feed the secondary panelboard!

If you have more questions, just let me know.
There's no way I would actually do the wiring, and have a licensed electrician (and friend) who will get the appropriate wire and do the job correctly on that end.

I am a trench digger only. Well, I will wire the CAT 6!

This is more or less about me digging through rocky ground as little as possible.
 

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