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E2 Electrician
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Usually one oversized conduit is plenty for communications cable's with an extra pull string left.
Absolutely not! each utility gets their own conduit. Besides, how are you not going to burn the existing utilities wire, if both are not pulled at once? Which is clearly not going to happen.

Don't they require a pull string to get their pulling cable in there?
Around my area, yes.
 

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Discussion Starter · #22 · (Edited)
The total length is 1800' and POCO will be pulling the 3 different runs while a chug a beer or 2. It's a single cable, more like a coax and I don't know the size. Maybe 2AL? That's what the drawing said. I have heard that on long downhill pulls the weight of the wire can overtake the friction and cause it to self feed resulting in a big mess at the bottom but I'm sure they know what they are doing. I said 7.2kv but that might not be accurate. The engineer told me 14 something but that may be line to line and not line to ground. Any ideas which voltage sounds more correct?

3" conduit for the power and 2" for a tiny 1/4" diameter phone cable. Overkill yes, but 2" DB60 was just pennies more than the smaller sizes of schedule 40 and it came in 20' sticks as with the 3". No chance for cable unless I run a monster feed and install a few amps along the way. Twisted pair DSL looks to be my best bet for internet maybe?? The POCO won’t pull unless it is backfilled. I guess they know about the static?

900’ is the shortest distance possible as there is no access for the trucks. She told me 1000’ is about the max but this is a fairly straight run although there is another creek I have to get through at the bottom of this hill. The only 90’s are the 2 sweeps coming out of the ground at the junction boxes. I chickened out trying to blow a string through it after I was done as I was having nightmares and panic attacks (slight exaggeration) about not being able to get something through after it was all buried. Instead, I have been running the rope and phone line as I lay the sticks. I have a 25’ leader of 12 gauge THHN so the rope and phone wire is staying out of the wet glue but it is a PITA dealing with the pull wire while trying to apply glue to the joints. There is another 500’ run through 2 more creeks and swampy wet lands that I did first and the conduit is probably (guessing) filled with water. It would require a large tow behind compressor to evacuate the water so I could blow a string through so that is another reason I decided to run the rope and phone cable while I installed the conduit.

P6260066.jpg


I'm also running a pull string through the phone conduit just because.

PB190017.jpg


High tech rope holder on the 500' run.

P8210021.jpg
 

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" Euro " electrician
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The total length is 1800' and POCO will be pulling the 3 different runs while a chug a beer or 2. It's a single cable, more like a coax and I don't know the size. Maybe 2AL? That's what the drawing said. I have heard that on long downhill pulls the weight of the wire can overtake the friction and cause it to self feed resulting in a big mess at the bottom but I'm sure they know what they are doing. I said 7.2kv but that might not be accurate. The engineer told me 14 something but that may be line to line and not line to ground. Any ideas which voltage sounds more correct?

[]
The POCO will make the final call which voltage they will use and I know the 7.2 KV and 13.8 or 14.2 KV is common one and they can be either line to line or line to netural depending on which grid they will tie to it.

With that distance more likey they will use armored alum cable simauir to our SWA cable which we used in France or they will use contrancted netural with either copper or alum cable so it will look pretty big the acutal size will depending on what they will use but for sure it will be about a inch diam no question asked

And with long run downhill we always like to run from the top and work it way down and yeah if not carefull it can overrun and can make a mess that why when we do the downhill pull we rig a drum brake or spool brake to slow it down ( the worst is vertical runs that is complety differnt story I will save it for other time )

With that long a run the last time I have 200 meter run ( about 650 feet ) I have use almost 50 liter worth of wirelube on that and when near end of run just stop ( or reduce it ) feeding the wirelube due it will actually fly pretty fast once the gravity take over.

Let the POCO worry about that when they pull the cable in the conduit they will know excat what to do with it.

Yeah expect to see some water in the conduit that is typical but you will need a tow behind air compressor to blow it out but let me give you a serious warning do not open the air valve super fast otherwise you will blow the plastique pipe apart so instead of that just ramp it up slow then crank it up and make sure there is no one standing on the opposite end of that conduit in case water or debries can fly out.

Bon Chance with your project.

Merci,
Marc
 

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they will use contrancted netural with either copper or alum cable so it will look pretty big
"Concentric neutral" - the big coaxial-type primary cable with the sprial-wound neutral shield to protect hapless diggers. [To use a word you taught me on here, contrancted is conneries :thumbup:]
 
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I think you can run RG-11 up to 1500' withought much loss but if you don't have any lines near you that won't help because of your 1800' run. One great thing is once it's all done most of this is their responsability.

Really wish I oversized my cable and phone wire conduit but I did not know they were going to drop off 6 pair 20g phone and RG-11 both cables were 3/8" thick. What a pull that was in the 3/4" conduit. Lots of lube and they went in though.
 

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Are you going with a pad mount transformer or a pole mounted transformer. What do they do with the cable between pull points install a pull box with manhole cover?
 

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Is it ever a problem that the pulled cable is overstressed and so becomes work-hardened, slightly and permanently stretched, and brittle?

Are there rules of thumb to prevent this?
 

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E2 Electrician
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Is it ever a problem that the pulled cable is overstressed and so becomes work-hardened, slightly and permanently stretched, and brittle?

Are there rules of thumb to prevent this?
Yes, every wire has a maximum pulling tension, this is why you have multiple pull boxes and minimum size required conduits... You can find these values I'm sure with google... The distance the OP went is unheard of around here...
 

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Discussion Starter · #35 ·
The POCO will make the final call which voltage they will use and I know the 7.2 KV and 13.8 or 14.2 KV is common one and they can be either line to line or line to netural depending on which grid they will tie to it.

Yeah expect to see some water in the conduit that is typical but you will need a tow behind air compressor to blow it out but let me give you a serious warning do not open the air valve super fast otherwise you will blow the plastique pipe apart so instead of that just ramp it up slow then crank it up and make sure there is no one standing on the opposite end of that conduit in case water or debries can fly out.

Bon Chance with your project.

Merci,
Marc
Thanks for all of the replies folks!


I'm 100% certain the outside shielding on the coax is neutral/ground with only one hot in the center. Not that it really matters other than I'm curious but does this mean the voltage is most likely 7.2 KV or there abouts?

Is it my responisibility to blow out the conduit? The power company never said anything about that part. I guess I better check before I call them out. Does it matter to them if the conduit has water in it while they are pulling?

I heard looking in the end of the conduit for the string while blowing the water out was the newbie's job. :whistling2: :laughing:
 

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Lic Electrical Inspector
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Is it ever a problem that the pulled cable is overstressed and so becomes work-hardened, slightly and permanently stretched, and brittle?

Are there rules of thumb to prevent this?
Yes. Which is why my Greenlee tugger has a meter on it for monitoring the pull.
 

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Discussion Starter · #37 ·
Are you going with a pad mount transformer or a pole mounted transformer. What do they do with the cable between pull points install a pull box with manhole cover?
It will be a pad mount transformer. They treat the pull points just like a transformer site. Once I level the ground up and lay down a gravel base they bring a 6" thick precast concrete pad that has the same dimentions as a transformer pad. On top of this pad is a green plastic enclosure I believe.

What is cool about this setup is if I ever want to build a powered structure close to a pull point they just get rid of the plastic cover and install another transformer at the pull point/junction box.

Here is a pic of a junction box/pull point. The right duct goes towards the hill I'm working on right now. The left one continues the feed towards the barn. The orange cover is to keep rattlers and mice out of the conduits as this is a weekend only project. You can see the red THHN pull leader sticking out of my phone conduit.

P2260006.jpg
 

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" Euro " electrician
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How deep is that trench? looks awful shallow.
Stickboy.,

If you did look at the photo there is a conventail 90 degree ell ( if you did see in the background then the bigger three inch is a wide sweep that is not the same as convential ell is.

IIRC the 3 inch PVC wide sweep is 36 inches high if you mesure bottom of the sweep to the top of the sweep so the OP is pretty much at 24 inches I will let the OP confirm this part to make sure.

In my neck of woods in Wisconsin if conduit with primary cable the shallowest they will allow is 2.5 feet but typically 3 to 5 feet down espcally with direct burial cable it will be more deeper toward to 5 feet marking.

In France it always more than 1 meter deep typically 1.5 meter deep unless you have a cable is not a SWA ( steel wire amoured ) type it have to be at least 2 meter deep.

Merci,
Marc
 
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