have used it previously (it was a belden powersum cmp cable) in limited fashion for a data installation and it certified ok, with no problems reported by the customer since (this was strictly a 100 megabit network).

now there's a situation where for a variety of reasons we may have to use this again, although in a more complex install that involves voice as well as data (up to gigabit), vga-over-utp (for projectors) and possibly serial-over-utp for enviromental sensors. it seems that we have to go the idf-to-mdf route, and using this as backbone between the floor boxes and the equipment room has been suggested.

i've used cat3 multipair as backbone in the somewhat distant past - but these were 10megabit nets. also used cat3 multipair extensively for voice. but this is a magnitute higher. usually we would opt for fiber or preterminated assemblies, but cost and simplicity is a factor here.

your opinion, if any?

I have used it for cabinet to cabinet data transfers in a large computer room. Honestly though I would have rather pulled regular cat5e 4 pair instead. Punching down cat5e multipair on patch panels was no fun.

Agreed. You are only talking about 6 runs of CAT5e 4 pair. For some of the things you mention, other than 4 pair under one jacket may cause you problems.

-Hal

+ the fact that the 25th pair will be physically 80% longer than the 1st pair. If you are at max distance with 4 pair, you'll probably have built-in problems with 25 pair.

The jacket on 4 pair will help prevent spillover.
Go with 4 pair.

Thanx for your answers. I agree too, that 4-pair is the way to go. So here's something to yet again reinforce the membership's opinions about IT people (and this from a former IT person): the IT guys somehow convinced management that they should get a first crack at the job...some genious found out about the multipair cable, thought it was a great idea, and the IT guys bought 2 spools of the thing. Then they realized there's more to cabling jobs than just moving patch cables around. We were called in...now the IT guys are sitting on 2000ft of cable (and are out a few grand off their budget) and are practically begging us to use it.
I don't mind accomodating them, if I can - any extra work will be billed. It's doing the install right that I'm concerned with. We just haven't worked with this type of cable enough to be absolutely, positively sure that everything will be ok (even if it certifies ok).

How many cat5e 25prs are you needing to run? From your description, it sounds like more than one.

I don't know what type of cable is best for serial/vga over utp, but seperate cables would allow mixing catx if necessary.

Jack

Tell your ITs that they have 2000' of wire that is not proper to use and if they insist have them sign a wavier to clear you if/when it doesn't work.

I agree about the waiver, otherwise you'll be stuck resolving the problems.

I would go one step beyond the Waiver , I would also send a letter to the man in charge informing him what you are doing

if there are problems do you think the IT guys are going to remember the waiver ?

Well, finally got the waiver yesterday, and later this afternoon we have a meet-up with some executive types to make sure they're in the loop (excuse the pun). It's funny in a way - where I'm right now I'm basically involved with replacing old multipair and RG59 with 4-pair cat6.
My thinking is that since this is strictly between frames as backbone, we'll terminate the 25 pair to different 110 blocks by function (ie one block for lan, another for voice, etc). Wire will be wasted, but they have enough

after your meeting this afternoon I would shoot off a letter to the "executive types " confirming what was discussed