Difficult cable pull thru conduit


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Old 02-05-16, 10:12 AM
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Difficult cable pull thru conduit

I have to pull multiple cat6 cables thru a 200ft underground conduit and then in the worst case up 5 floors.

The conduit is four inches, but, due to the length of the run and presumably the hard 90s it makes, even 6 cables cannot be pulled at the same time.

It's beginning to become apparent that another conduit needs to be run, but I still haven't use this conduit to some extent.

I have cable lubricant, I'm buying a second and third box of pull string to run multiple fishing lines.

Are there anything else I can do?

I've also tried taping the first 50 feet or so to keep it thinner and reduce friction, but that appears to have been counterproductive.

Any help is much appreciated.

Presently, I've pulled out 6 cables after almost 300 feet when it just stopped moving, and I'm down to trying 2 at a time.
 
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Old 02-05-16, 10:19 AM
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I have moved you to electrical since electricians are most familiar with cable pulls.
 
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Old 02-05-16, 11:05 AM
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Have you gotten a pull cord through the conduit? If not I tie a small piece of cloth or foam ear plug onto the end of kite string and blow it through the conduit with a leaf blower or shop vac. Then use the string to pull a stronger pull cord.

When a conduit is going to be stuffed and there are curves I pull each cable separately. Trying to pull a whole bundle at once is tough and if you tape them together it can make it difficult to get them through bends. When it's going to be really tight I send through one pull cord for each cable and get all my pull cords in before pulling any cable. I lay out all my pull cords so they can be fed in without tangling and have someone slowly pull the first pull string while a helper insures that the multiple pull cords go in neatly, usually by laying one cord between each finger (gloves are a good idea). Then lube up your cables and start pulling them one at a time.
 
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Old 02-05-16, 11:13 AM
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Thanks for the reply. I do have a pull cord, and a box of pull string to replace it as I go.

I also bought a 240' snake in case I lose one, as I almost have a few times.

I'm going to employ a slightly modified vetsion your advice, pick up another box and try to pull 2 at a time as described. The conduit is 4", so at first I hope at least that wud be possible.
 
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Old 02-05-16, 11:21 AM
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How many elbows/bends do you have in the entire conduit run, it sounds like you may have more than 360 degrees in bends. 6 cables should just about fall through a short 300 foot run of 4" conduit.
 
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Old 02-05-16, 11:35 AM
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From the headend it goes down, there seems to be a 90 degree right there. Then it ends up almost 200 feet away and about 10 feet higher. I suspect there is another 90 there.

I'm also surprised that with the lubricant it is still so hard to pull. Either there is a bend underground or two, or it's just all the friction due to the length. This is the first time I've tried to pull through a conduit even close to this long, so I don't know which is right. Maybe it's both.
 
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Old 02-05-16, 12:08 PM
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Conduit is supposed to have no more than the equivalent of four 90[SUP]o[/SUP] bends between access points. All bends are supposed to be long sweeping bends. I suspect that what you have is NOT conduit but water pipe with short radius water pipe elbows rather than conduit bends.

Something else to consider, Category 6 cables have a maximum length of 100 meters or about 330 feet. Sometimes they will work in longer lengths but often you will experience data loss or even total failure at any excess length. It reads as if your length will be such to cause concern. Secondly, if this is an underground run or if the conduit ever goes outside or through an unconditioned area there is a significant chance of condensation forming in the conduit. If this is true in your situation then waterproof cable needs to be used.

And why so many cables? One cable with a router or switch will work just as well in most situations and the router/switch starts you all over with an additional 100 meters of length downstream.

Have you considered fiber optic? Fiber will run LOTS farther than cat. without needing a boost.


Oh, when pulling either cables like Cat. 6 OR individual conductors they are ALL to be pulled at the same time or a condition called "braiding" where the individual cables or conductors end up twisted around other creating a big fat knot that will REALLY get your blood boiling when you need to yank them out and start over.
 
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Old 02-05-16, 12:44 PM
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`I really hope some knucklehead didn't install an LB instead of sweep 90's. Data cables have minimum bends radius that needs to be preserved.
 
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Old 02-05-16, 10:58 PM
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Oh, when pulling either cable like Cat. 6 OR individual conductors they are ALL to be pulled at the same time
I'll agree with that 100%.

Here's another thing to consider..... standard data cable is not rated to be installed in wet locations. Underground conduits will get water in them. The water will leach in and ruin that wire. I ALWAYS use gel filled data cable in underground pulls.
 
 

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