Cable types or class.......

[wateck]

I am a low voltage technician in WA state. I have o co-worker who is trying to pass the Journymans Exam, but is really struggling. He asks me all the time about D- Cable and M- Cable...I passed my test 4 years ago, but I have no idea what he is talking about. I have looked and searched and read trying to find the answer for him........hope on of you kno what these designations are.

Thanks

[hbiss]

I have no idea either and I have been doing telecom and LV for over 30 years.

Doesn't he have a study guide or a reference list for the material on the exam? Where is he getting the D and M cable questions from? Maybe the context of the questions would give us a clue.

My sneaking suspicion is that this is some kind of BICSI jargon. :roll:

-Hal

[frenchcomp]

Have a look at art.310 NEC 2005:
(C) Suffixes to Designate Number of Conductors. A type letter or letters used alone shall indicate a single insulated conductor. The letter suffixes shall be indicated as follows:
(1) D — For two insulated conductors laid parallel within an outer nonmetallic covering
(2) M — For an assembly of two or more insulated conductors twisted spirally within an outer nonmetallic covering.

[hbiss]

Same in 2002 and I suppose that's as good an explanation as any but what does that have to do with low voltage cables?

-Hal

[cosmos]

ISO/IEC 11801 classifies twisted-pair as A(cat. 1), B(cat. 2), C(cat.3), D(cat.5), E(cat.6), and F(cat.7).