atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring IT guys strike again!

"As long as its the same on both ends it doesn't matter." I've heard that one a few times before. LOL

I've heard that one too many times, too. Those people also rarely have any idea why we use twisted pair.

There is a major difference between installing a telephone system WITH its associated wiring and installing a generic Structured Wiring System.

Years ago we would install various data systems and each one required a completely different wiring system.

IBM - RG-62 Coax
Dec - 2 pair 24 AWG with MMJ jacks
Starlan - 2 pair AWG 22 with RJ12
Ethernet - Either "Goldenrod" or RG-58 Coax
Wang - Dual coax with BNC and TNC connectors
etc.

Every time a customer bought a new computer system they had to change their wiring. The EIA/TIA 568 structured wiring standard was designed to eliminate this problem for customers by creating a standard network wiring that all DATA system manufacturers could agree on.

All DATA systems.

While the 568 standard addresses voice wiring and recommends the same 4 pair jacks and cabling I would like to say, that I am unaware of any telephone system (with the exception of 1A2) that won't run on a 3 pair 24 AWG Cat3 cable with 6P6C jacks.

DEC created the MMJ jack so that you wouldn't confuse their connections with anyone else's. There is a certain logic to this. I'm sure most (if not all) of us have gone on service calls where people have plugged their phones into data jacks and vice versa.

If I had to recommend a wiring scenario for a customer it would be Cat-something (5E,6 6A - whatever they wanted to pay for)for the Data and Cat 3, 3 pair for their telephone system.

Sam

AT&T Merlin will run on only 3 pairs? I've never tried it, but I thought they used all 4.

Yes, the Merlin systems would run on three pairs (voice, data and power), but the absence of the white/brown pair meant that there was no hands-free intercom (HFAI). Intercom calls had to ring at the station.

No HFAI would be a deal-killer in some installations.

Probably way off topic, but I was called in to troubleshoot a data installation completed by the electricians a few months ago. When they couldn't get it to work, their CG took a shot at making it work. Then, they called me.

No Patch panels - everything terminated on 8P/8C Plugs and plugged into the switch. Looked at the terminations and found out that they had terminated 568A on one end and 568B on the other end - because "there has to be an A end and a B end". That made me decide to take a closer work at the install in the rafters. Found about a million wire staples on the CAT 5e runs - all hammered staples!

Long story short - I wound up rewiring the entire office suite properly above the drop ceiling and selling a new phone system.

ED

As I have said a million times: Just because their licence says they can do it, doesn't mean the should do it.

One question Ed...Did the customer get their moneys worth in the overall cost to complete the job?

I just remembered the network installation I looked at back about 10 years ago that was botched by a Verizon tech. (He was doing a side job). He punched the wires to the patch panel in the wrong order. He happened to be there while I was looking at it and he repunched them the right way...problem solved.

Dean,

I think so, because the customer wouldn't pay the contractor for that work. I thought it would cause trouble for the contractor, so I took an hour and went m by and met with them. When I finished showing them the photos before and after - there were no questions asked.

Got a call today from that contractor to do their new office cabling.

Ed