I will be running power to my workshop-under-construction soon. I wanted to run water also, but have many obstacles (trees, driveway) to snake around…plus the shop won’t always be heated in the winter and I’m afraid of freeze up….sooo I’ve decided to cop-out on the water supply and just go electric, cable, phone and propane gas line in a 12″ deep ditch. Do I need to put these in a PVC pipe for protection, or can I just bury the stuff as is? Can I wire tie everything to the copper gas line? <!—-><!—->
S <!—->
Replies
Electrical wiring has to be either approved direct burrial cable and it has to be 24" deep or it can be run in conduit and at least 18" deep.
Thanks Bill...what about phone lines, cable and such? Any restrictions? The gas copany said I neede to go 18" deep for their line..flex copper.
I don't know if there is code for the cable and phone. If it is then I would assume the same as for power.
No code (at least not a standard one) for cable and phone -- just whatever the fone and Kable companies might require. Otherwise, you can lay it on the grass if you want.
There is a way to go shallower with the electric if you put concrete over it. PITA, though, so go deep if you possibly can.
Keep cable and phone at least 6" away from the electric (to prevent interference pickup), and keep gas and electric apart (probably there's some code on gas-electric separation distance).
just whatever the fone and Kable companies might require
And, half the time, they just want to string coax building to building <shudder for one too many previous bad experiences>
My preference is to seperate cable coas from phone lines by at least the width of the ditch. The OP would probably be best served by running NMT for either, so that, come the revolution, there's no digging up or just abandoning cables underground (but I'm cynical on all things telco just now).Occupational hazard of my occupation not being around (sorry Bubba)
why not just get a cordless phone
get a cordless phone
One more thing to lose in the shop?
Besides, he really didn't ask the important question--how to get the broadband for BT into the shop and not the house . . . Occupational hazard of my occupation not being around (sorry Bubba)
Bill Hartmann is right again. The only thing I would suggest is to sleeve any lines you have through a pvc conduit. Lots of luck.
You can bury in same trench, however I would recommend that you seperate gas and electric at different elevations and opposing sides of trench. Just in case you ever have to dig in service area you would not cut both lines at once and possibly create large boom.
Seen it happen and it wasn't a pretty picture
Thanks for your replys
Sooo...If I'm reading this right, I need to bury the lines at least 24" deep in a 12" wide trenchand route each line through PVC positioned opposite from the gas line in so as to avoid electrical interference and possible explosions. Gee...and I thought this part would be simple. I was hoping to just route all lines through 4" PVC and bury.
S
No, 18" with it in conduit.
It's not legal to put low-voltage lines and power lines in the same conduit. Also, not a good idea from an interference standpoint. But if you use steel conduit then you can put them right next to each other with no interference worries. In plastic (or bare wires) you need to separate them a few inches. Six inches in air, but probably 3-4 in dirt is sufficient.
Dan,
What's your basis for saying low-voltage (signal) and power wiring (less than 600V)can't "legally" go in the same conduit? Do you have a Code section?
Cliff
My code book is old (1981), so the section numbers probably won't match, but in 800-3(a)(2) "Communications circuits, separation from other conductors":Communications conductors shall not be placed in any raceway, compartment, outlet box, junction box, or similar fitting with conductors of light or power circuiits or Class 1 circuits.
I'm not current either, but at least I'm 18 years more up-to-date (1999 NEC). 820-52(1)(b) "Coaxial cable shall not be placed in any raceway, compartment, outlet box, junction box, or other enclosures with conductors of electric light, power, Class 1, ...."
800-52(a)(1) says the same thing for communication cables.
However, given who is questioning this, are we misreading the code ?
r--
You've got the right Code section, which in the 2002 Code is also 800.52, but read the first paragraph:
"Communications wires and cables from the protector to the equipment or, where no protector is required, communications wires or cables attached to the outside or inside of the building, shall comply with 800.52(A) through (E). " (italics mine...)
And as you pointed out, (A)(1)(c) says that the communications conductors cannot be in the same raceway, box, etc. as light or power conductors. But that prohibition is modified by the paragraph quoted above, and the way I read it, that changes everything.
My interpretation of this is that the italicised section allows me to run power and comm cables together (in a box or conduit), as long as the power and comm cables are in separate conduits or boxes after a protector.
For the non-telco people among us, the protector is basically a lightning arrestor and overvoltage guard, and for your telephone lines, it's in the network interface device. However, you can buy and install your own protector (and if you live in lighning country, it's a very good idea to protect the low-voltage lines between buildings at the point of entry to each building--even underground lines can pick up quite a bit of energy from a lightining strike. There are protector modules that don't cost much, install easily, and offer pretty good defense against stray energy pulses). CATV installations use a lightning arrestor device as a protector.
So, in an underground conduit leading to a junction box on the exterior of a building, power and comm cables/wires can be run together and meet Code. The power and comm cables must diverge before the wires land on or enter the building, and the comm wiring must go to a protector.
Also, to share a conduit, the insulation of the comm cable must have the same voltage rating as that of the power cable.
Now, for S's situation, where he can bury two conduits, I agree, I wouldn't recommend running power wiring and tel or CATV cable in the same conduit, for reasons others have mentioned--the 60Hz noise on the comm signal.
But I mention this option because there may be an instance where someone has no other choice but to run power wiring and comm cables together in a conduit, and if they used (a) protector(s) and appropriately voltage-rated cat 5 (or higher) cable for the phone and quad shield for the CATV, it'd be Code-compliant, and it'd probably work fine.
Cliff
Edited 7/6/2005 9:48 pm ET by CAP
One thing useful for any trench is a tracer a foot below grade to aid in finding buried stuff later, many use a white single 14awg. I tend to use old car fenders, rusted out pipe, plasterboard and pt lumber scraps, scrap carpet, old computer monitors, etc. Saves on dump fees too!
"My interpretation of this is that the italicised section allows me to run power and comm cables together (in a box or conduit), as long as the power and comm cables are in separate conduits or boxes after a protector."But 800-10 & 800-11 cover conductors outside the builidngs and require clear separation.800-11 Under ground circuits Enering buildings. (a) with power conductors - "shall be in a section separated by brick concrete oer tile partions or by means of a suitealbe barriers"800-12 fro circuits requiring primary protectors. I don't ahve the time to figure if a primary protector is required inthis case.But it requires 4" separate between communications and power wires unless one is in a conduit.
Bill,
If the comm cable running in the UG conduit with power wiring terminates at a protector before entering a building, then I believe 800.11 does not apply. The point being that the comm cable in the conduit with the power wiring ends at the protector, after which a separate comm cable enters the building. It's not the same cable...
The protector is a dividing point, and it provides protection from accidental faults between the power and the comm wiring.
The requirements of 800.30 apply, as far as the type and application of protective devices. It's interesting, that section also requires protection at both ends of an UG cable run, unless the cable is less than 140' and is in metal conduit or has a metallic sheath bonded to the buildings electrode systems, or unless it's in a high-rise area or in a low-t-storm area.
If there are no protectors, I completely agree with your interpretation--no sharing of conduits, boxes, etc. It's not a great idea anyway, but like I said, there are arrangements under which comm and 120V-to-ground power cables can share a conduit and still be compliant. At least the way I read the Code.
Cheers,
Cliff
Interesting. I checked back in the textbook for my electrical classes (I'm not a pro), which was Ray Mullin, "Electrical Wiring Residential, 13th Edition". Page 441 says "Telephone wiring is not to be run in the same raceway with electrical wiring. In addition, it cannot be installed in the same outlet and junction boxes as electrical wiring." (Italics his). He then makes a general reference to Article 800. But I realize you know your stuff, so I will do more research.
I had similar questions a few years ago when developing my property. Seems, on the face of it, to be simple. BUT, You mentioned trees. How big are they and what species? Many don't take well to having thier roots cut by the trenches, not to mention damaged trunks from the back hoe, and long term damage from compaction and top & subsoil disturbance. You might want to consider some strategic removal now to straighten the path of the trench...for the ones that will die in a few years anyway from the damage.
Also, do you have signifigant rock in the area? Have you ever seen a trench back-filled and the kind of impacts that rocks can make on cable, lines, etc? Probably one of the reasons for the specifications of conduit etc.
Also, if you are using rigid metal conduit, I believe Table 300-5 allows you to just bury it 6 inches, as long as you are going around your driveway, and not under it. But given your obstacles to snake around, and the gas company's requirement, this probably won't be of help to you.
Wow..talk about information overload...I'm getting dizzy....but seriously, I appreciate all the responses....After pondering your options/requirements I took another look at possible trench routes and have decided on a more direct approach that will pass between 2 big..but dying ash trees that anchor my wifes sacred Nagshead hammock. This is practically a straight line (130') to the workshop with a couple of 45's to end at the desired 6x6 where all hook-ups will take place. I can also now reconsider going deeper for a water line. This rout was out of the question until she found a couple other maples that would suffice when the ash finally die.....The cordless phone was a good idea...but still unsure about using conduit or PVC..or as one suggestion....nothing..just bury the wire, gas line and cable in the trench and spread them apart before backfilling. Not that it matters I guess, but I live in the country and out of reach of code restrictions...but I still want to do it right.
S
If you talk to the utility companies, they will probably give you their spec sheets for underground conduit. They will also give you info about depth, separation, etc.
Since trenching can (and will) cause significant damage to tree root systems, look into directional boring. It's far less invasive than trenching and 150' can probably be done in less than a day.
What is directional boring and who does it? How much space around the boring point is required?
Directional boring is a construction technique that essentially bores an underground hole between two pits. The boring machine needs a space about 10' x 10'. It has a cutting head that is attached to a series of pipe segments and can be "steered" by the operator. After the head reaches the receiving pit, you tie one or more ducts(HDPE) to it and pull the head back to the boring machine thus laying your conduit.
Most underground utility construction companies have boring machines - or have boring companies on their subcontractor lists. Check your local Yellow Pages.
Thanks!!! Can directional boring be done from say, a basement to a pit, or will the machine likely not fit through the door? I'm guessing that you have to know where existing utility lines are too, to avoid damage.
If you have a place for them to setup I suspect that they could start in the middle and bore each way.May nee a "man hole" at that point to join the two. Or dig a pit.
Some of the smaller machines may go thru a door but I sure wouldn't put one anywhere I wanted to keep clean. I may have failed to mention that it's a VERY messy job. - lol If you find someone who does boring, just show them where you want the ducts and how many ducts you need then let them figure out the best way to do the job.
Don't forget to check with the various utilities about duct depth (they may call it "cover") and any separation requirements. Around here, power and phone are often placed in a joint trench (both utilities own the trench/bore). I once engineered a job with sewer, storm drain, reclaimed water, power, phone, and ducts for ten fiber companies in one humongeous trench. Man, was that an exercise!! - lol
Oh yeah. Whether you trench or bore, make sure you make a GOOD as-built drawing showing the path of your ducts, the depth, and the location of any joints. You may never need it, but someday, someone will.
Edited 7/7/2005 7:58 pm ET by Dave
And if you trench, take pictures, including some landmarks in every picture so that you can figure out where things are later.
Good point, Dan. When I was designing and building telecommunications duct structure, my "final package" was a complete set of as-built drawings and beaucoup digital pictures of the job. The customer got the CD after the final bill was paid. - lol
have boring companies on their subcontractor lists. Check your local Yellow Pages.
Hey, our local sub for that is under-exciting, but not boring <g>.
Look under "Utility Contractors," that's where the line contractors are usually listed. If not, call the electrical contractors and ask them if they know if anybody locally does u/g boring (they are likely to, if they've been on a job where the local utility had to bring power under a street to hook up a new building).
The start & stop points will need a pretty good sized hole, and in front of the 10x10 "spot" for the machine. You want a spot that not only will 10 of tracked machine fit in, but the 16' trailer with water to "power" the cutting head, too. There's a minimum diameter for the tube pulled, too, and I want to say it's 2" diameter. They can run the tube pulled "long," so that the holes can be dug with a mini excavator or the like up to where they need to finish.Occupational hazard of my occupation not being around (sorry Bubba)