atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Service Loops

You can do service loops and keep them neat and it doesn't have to take any extra time or effort. What I do is to install my pipes and insulator rings then all the cable drops go down through them plus 12 feet more than is needed. 10 for the loop, 2 for working room. They are all appropriately tagged with numeric strips. That would be the concentration point. At the wall side, you simply pull out about 10 feet more than you need then make a nice neat loop in the ceiling. You typically will have 4 cables, sometimes 6 so it's easy. A couple of zip ties and you're good to go. Now back to the concentration point. Once you have all your cables run you climb up into the ceiling space and pull back the excess making a nice large loop. I can typically loop 18 or so cables at a time without them becoming too unweildy. Then I secure them onto j-hooks I have installed just for this purpose. I get excellent strain relief, no pinched cables and plenty of support. Now if the ceiling space is very low then an 8-shape lying on its side is the best solution. I like to use a large bridle rings for this.

Either way it really takes no extra time at all. It burns through a lot more cable but the specs call for it and I feel it is a mark of a quality install. Few people can know the difference but the few who can, can make your life miserable.

i am an old general telephone guy. we never used service loops but i do now for the reasons mentioned above.

We have gotten in the practice of using a sections of cable tray say 5' in length above the rack, making basically an S shape with the cable. Gives it a clean look like you spent alot of time on it (not) and you can then strap your cable bundle to the cable tray to keep it neat. As far as needing loops, I have yet to need one at a rack but yes at the jacks, only takes one time swearing cause you only have a few inches to get reterminated to want that extra couple of feet.

It's been my experience that those who don't test their work, don't leave service loops. This is just a rant... it's inevitable that I have to end up running a new cable because so many fly-by-nights pull taught and staple everything like it's going out of style.

This was a good question. I, personally, leave a service loop all the time... it's going to do more good than bad. Really, they don't do much bad at all. I leave about 8' and tuck.

Could it be that service loops began as a "How can we sell %10 percent more product"?

This is a question I feel compelled to ask the forum.

That's what they want you to think, but it's really for national security. All those extra loops are there so the gov't can install microphones and spy cameras once Bush is re-elected.

It's become the norm for many of the reasons stated. However I for one haven't had to move a patch panel, or blocks. I really doubt anyone does it because they can get a few more bucks off the cable. Could be wrong though.

We only leave service loops on our OSP cables. I will leave a little copper in the handholds but mainly fiber.

If it's inside we may leave a foot to 18" in the wall at the outlets, but thats it. None in the closets.

Although the exact amount of required cable slack depends on the size and layout of the
connecting hardware at the TR or TE and the work area, the recommended minimum
amount of cable slack:
• At the TR or TE is 3 m (10 ft).
• In the suspended ceiling for the telecommunications outlet is 1 m (3.28 ft).
NOTE: If a horizontal distribution method other than ceiling distribution is used, the length of
recommended minimum amount of cable slack should be adjusted accordingly

Reprinted from TDMM 11th Edition
Page 4-71

Jeff

I have recently done some new cat5 runs for the three walgreens stores in town here. I wish the original installers had left something of a service loop. They all have 5 1/2' rolling cabinets within the pharmacies, no problem getting the wire down the wall with the existing pipe and a 12x12 j box but getting the rolling cabinet more than a foot from the wall was tough. Just enough room for me to squeeze between the shelf and the cabinet. But then these jobs are spec'd from the company when the building goes up. Funny thing, two of the buildings were finished in the last 6 months,thats some foresight.