sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring Lots of "service loops" ?

I spent the day cleaning out very old data cables from the ceiling of a private school. Another company got the job to recable most of the school with cat5e. On the surface it looks like they did a pretty good job. They used wide J hooks to support their cables, they fished inside of cider block walls and used good surface mount jacks. They numbered every thing. What bothers me is at the top of the wall for every run they left a coil of wire taped together. I estimate the coil to be around fifteen feet in length. At the rack they have two coils of wire in the ceiling bigger than a roll of garden hose. I estimate the coils to be around 30 or more feet in length each. This is an extra 50 feet of wire to every drop. Am I missing something here? Why would a decent cable company who uses a DTX certifier risk EMF with a bunch of coils of cat5 in the ceiling of an old building full of old wire? Is there some advantage to this (other than a move later) that I don't know about?

I've run into that, too, here lately. We were asked to bid on finishing a job for a courthouse and were shown what had been done so far---and there was a massive amount of extra CAT6 cable coiled in the equipment room and 10 or so feet of cable at each jack location. This was all supposed to be certified. We just nodded all during the walk-through and politely did not even bid on the job. Too many stringent specs that couldn't be complied with and then the fact that they accepted that kind of stuff. Maybe there's something we don't know about either.

Just a note: the last job we did to "clean up" old data cable ended poorly-- by the customer paying 2/3 of our invoice---because "not much was done". The cable job went to someone else. Very frustrating. I can't wait to see what kind of quality the cable installation is going to be. done.

service loops won't keep a cable from certifing, but it is a waste of cable and a bit unsightly, especially on the rack side. We usually do put a service loop (small) at the jack side, but never the rack side. We always dress in the rack. One of our customer sites that we took over recently has the same thing on the rack side, except its probably 100 extra feet, not even coiled nicely, and 6 racks. I could go into what happened, but that would take too much.

50 ft is excessive i always leave prob 10-15 feet in the ceiling above the jacks and then route the cables the long way around into the patch panel so theres 5 feet or so of play

I do believe those who spec long service loops at each end were just "boiler plating" a spec they came across or had been given. It's wrong thinking and unfortunate this practice continues.

I ran a huge job for Time/Life in Rock Center a number of years ago. The spec for the job included 20' service loop at every work area. I questioned it and never got an answer. After the job went in the IT guys said that they requested it "so they could move the jacks if they have to".

Mind you, all the jacks were flush mounted into electrical boxes mounted in the wall.

I advised them that pulling the jack out of the wall and shlepping it along the floor violated the EIA/TIA 569 spec and negated all the certification. They just shrugged.

These were the same guys that wanted the telephone cables terminated on patch panels.


Sam

Every IT guy I've tried to reason with on this gave the same reason Sam just related to. "We may need to move it someday". Makes no sense to me. Even over the racks, if they do want it moved "someday" no amount of slack will be the right amount.

When I was working for a sound company we made sure to leave 5-10 feet in the racks for mic and speaker cables, just in case they needed to move/replace equipment. Having to work on equipment where there is two inches of wire is pretty tough.

Jeff -

Moving equipment is one thing. We assume that amps will occasionally need to be replaced. But jacks and/or panels that have already been tested and certified? I can't remember doing that more then a handful of times in 40+ years - unless there was water, fire or some other external type of damage. I can't see making a mess on every job for the once-in-a-blue moon disaster.


Sam

I always left 5' of wire in a loop above the jack. "YA NEVER KNOW" what some idiot is going to do to the jack. Saved my bacon maybe 1/2 a dozen times in 30 years!

I do remember being glad the installation guys on one job were REAL sloppy with 25pr feeders in a 60 station electronic system. The maintenance guy moved a panel and a humungous pile of grey 25 pair cable, from the replaced 1A2 system, fell on him. He got upset and started chopping indiscriminately at cable. Naturally color didn't count. Our 'sand beige' cable got the axe, too. I was able to put AMP ends on most of our cables and get the system back and running within 2 hours. Most of the time for my partner was spent running around town trying to find 60 0.315A fuses. Did you know 3/8A is 0.375A and woks just fine on the old Meritor systems?