Burying CAT6 in pvc conduit- direct burial rated cable needed?

[Jessie.slimer]

I think I know what everyone will say- use direct burial rated cable because the pvc conduit will inevitably fill with water, but I am asking anyway.

I am going to dig a shallow trench from my house out to my mailbox (about 110 yards) to put a couple of cameras out there and bury a 1 inch pvc conduit so I can fit a few cat6 cables inside. On the house end, I plan to put cat6 to fiber adapters and a short piece of fiber between the house camera network and the mailbox camera poe switch to isolate and protect my house electronics. Point to point links at the mailbox and house are not an option due to tree obstructions, and a there is no power out there so a full fiber run won't work either.

Do you think the gel filled cable is necessary? Or can I get away with regular cat cable?

 

[wittaj]

You know the answer LOL.

Does it mean that people have used regular cable and have been fine - sure.

Comes down to your risk and acceptance LOL. Maybe regular cable lasts longer than you do or maybe it goes out in 2 years.

 

[tigerwillow1]

I'm going on 5 years with a couple thousand feet of CMR rated indoor cat6 in buried conduit, with no failures inside the conduit. Much of my land is sloped and wherever possible I was careful to lay the conduit without low spots that would trap water, allowing it to drain to the low end. The flat runs are surely filled with water by now. I have had two issues to deal with. One is that the indoor cable exiting the conduit does not tolerate sun exposure very well at all. I've gone to covering those parts with 1/4 in split loom tubing. The other problem, unrelated to the cable type, is with several underground splices inside buried boxes with removable covers. The splices get hammered with condensation and one or twice a year I have to deal with a failure. I agree it's a risk/reward situation. I figured if I came out on the losing end I could always pull new cable through the conduit. A pain for sure, but nothing compared to all of the initial digging. I used 1-1/2" PVC in the runs with 6 cables, then 1-1/4" where it splits out to fewer cables. With the way the PVC prices have skyrocketed, I must have about $1,000 worth of it buried.

 

[HereBull]

I can add to this as well, using indoor rated Cat5e I put in 3/4 and 1/2 conduit in 2008 - I am almost positive the cable has been sitting in water in those tubes the entire time now and they still pass with a certifier. Is it proper or code? Absolutely not.

As mentioned above, risk tolerance. If I were doing this on a job or commercial project, gel filled or the new gel strip type cable all the way. Honestly though anything that starts to get crazy on conduit runs between buildings or such, I prefer fiber anyway, if I can slap an outdoor NEMA enclosure near a bunch of cameras I'll throw a fiber switch in there and do fiber backhauls (assuming power is readily available).

 

[tigerwillow1]

Is it proper or code? Absolutely not.

Gosh, to meet code the cable or conduit usually has to be 18" or 24" deep. I haven't noticed any forum people going that deep. One of my thoughts is to just yank it all out when selling the house.

 

[HereBull]

Gosh, to meet code the cable or conduit usually has to be 18" or 24" deep. I haven't noticed any forum people going that deep. One of my thoughts is to just yank it all out when selling the house.

The last few times I've had inspectors out to check my bigger solar projects where I did indeed go the right depth, they didn't even bother ensuring it was to code - 5 minutes glancing at everything and signed off. Although there is some peace of mind, especially when crossing a driveway or other area where going that deep makes sense.

 

[Ri22o]

Gosh, to meet code the cable or conduit usually has to be 18" or 24" deep. I haven't noticed any forum people going that deep. One of my thoughts is to just yank it all out when selling the house.

I literally just got done burying 70 some feet of conduit 18” deep.

 

[Ri22o]

 

[TonyR]

Just be aware that direct burial-rated CAT cable's outer jacket is generally thicker PE or HDPE insulation which will take a lot more physical abuse than the PVC outer jacket of CMR...meaning you must be careful not to accidentally slice, slit or split the CMR's outer jacket when pulling it in.....even dried glue in the joints and tiny rocks that can damage the jacket on CMR most likely wouldn't faze a direct burial or flooded burial jacket....so just be more cautious when pulling the CMR in.

I'm usually in such a hurry because of so many irons in the fire I know I won't be that patient and opt for the cable with the thicker and more expensive jacket rated for direct-burial....but that's just me....YMMV.

 

[juliand]

no codes here for residential low voltage burial, at&t like companies just part the grass with a square shovel and lay their line in, and step back down on the sod.
I glue up and bury about a foot deep, grey pvc for my cables and never have a problem, just sweep up and seal up your ends or use a box. while you're at it, run an extra piece of string in the pipe for future wires. - dont think it too hard

 

[tigerwillow1]

no codes here for residential low voltage burial, at&t like companies just part the grass with a square shovel and lay their line in, and step back down on the sod.

I'm not saying you're wrong as I don't know what code you're subject to. I do remember that there's somewhere in the NEC that says in essence utilities are not subject to the codes but instead follow their company procedures. Some of the professional outside wiring that passed inspection at my house isn't even close to meeting code. One example is a 100 amp feeder to the shop with the top of the conduit about 5" deep. It's full of gouges from the landscaper's tiller.

 

[Holbs]

You get one shot at putting this cable in the ground. Do it right. Get underground gel filled Cat6.
Sure, there 10-20 folks here that say no problem, has been ok for 10 years.
I could list you 2000 other folks who had a indoor cable that was used outdoors in pipe or directly into ground that had the hassle to replace 2-3 years later.

Feel like gambling? Goto Vegas.

 

[Flintstone61]

@Ri22o , hopefully the neighbors don't think there bodies going in.

 

[Ri22o]

no codes here for residential low voltage burial, at&t like companies just part the grass with a square shovel and lay their line in, and step back down on the sod.
I glue up and bury about a foot deep, grey pvc for my cables and never have a problem, just sweep up and seal up your ends or use a box. while you're at it, run an extra piece of string in the pipe for future wires. - dont think it too hard

I'm not saying you're wrong as I don't know what code you're subject to. I do remember that there's somewhere in the NEC that says in essence utilities are not subject to the codes but instead follow their company procedures. Some of the professional outside wiring that passed inspection at my house isn't even close to meeting code. One example is a 100 amp feeder to the shop with the top of the conduit about 5" deep. It's full of gouges from the landscaper's tiller.

NEC rules all. Local codes can only be more strict, not less. So if NEC dictates an 18" burial depth for wires in PVC conduit, that's the depth.

@Ri22o , hopefully the neighbors don't think there bodies going in.

Or maybe it's better that they do...

 

[tigerwillow1]

NEC rules all. Local codes can only be more strict, not less.

Not true. It's states, counties, and cities that have the authority to regulate. Most adopt the NEC, often in a modified form. I'm reluctant to use wikipedia as a reference, but it's introductory paragraph is right on. It's all about the Authority Having Jurisdiction.

The National Electrical Code (NEC), or NFPA 70, is a regionally adoptable standard for the safe installation of electrical wiring and equipment in the United States. It is part of the National Fire Code series published by the National Fire Protection Association (NFPA), a private trade association.[1] Despite the use of the term "national", it is not a Federal law. It is typically adopted by states and municipalities in an effort to standardize their enforcement of safe electrical practices.[2] In some cases, the NEC is amended, altered and may even be rejected in lieu of regional regulations as voted on by local governing bodies.

 

[Holbs]

Put your 12vdc or 24vdc 1" deep in the ground. Who cares. PVC conduit, EMT conduit, direct underground...there is no NEC code application in this case when it comes to a homeowner doing his thing. I have 24vdc running 100' out to my lamp post in 6" depth using underground solid core Cat6. No NEC police coming at me.

 

[TonyR]

Not true. It's states, counties, and cities that have the authority to regulate. Most adopt the NEC, often in a modified form. I'm reluctant to use wikipedia as a reference, but it's introductory paragraph is right on. It's all about the Authority Having Jurisdiction.

The National Electrical Code (NEC), or NFPA 70, is a regionally adoptable standard for the safe installation of electrical wiring and equipment in the United States. It is part of the National Fire Code series published by the National Fire Protection Association (NFPA), a private trade association.[1] Despite the use of the term "national", it is not a Federal law. It is typically adopted by states and municipalities in an effort to standardize their enforcement of safe electrical practices.[2] In some cases, the NEC is amended, altered and may even be rejected in lieu of regional regulations as voted on by local governing bodies.

Agree 100% ^^.

The sad and unjust thing is that the NEC can bring pressure (when they are pressured by higher-ups) upon a City or State by having another Federal bureau withhold certain Federal funding in a totally unrelated area IF that City or State doesn't comply or incorporate the NEC specs. It's their way of making themselves self-important.

I recall, I think it was late 79's or early 80's, the NEC threatened to withhold funding to any agency in the State of CA that continued to use a traffic signal conductor with green insulation for anything but earth ground. At the time we had red, yellow and green wires for...you guessed it...for the 120VAC red, yellow and green traffic signal indications, white was neutral and earth ground was bare copper. It is a controlled-access situation, only permitted and certified individuals allowed in the traffic signal pull boxes and cabinets, but the NEC prevailed, the hot for the green traffic signal was changed to brown insulation....everyone BUT....you guessed it again....the railroad! They could color anything anyway they desired...it's impossible to out-bully an experienced bully.

 

[tigerwillow1]

At the time we had red, yellow and green wires for...you guessed it...for the 120VAC red, yellow and green traffic signal indications

Way too logical for today's world!