Tag and subject changed

On Thu, 16 Sep 2004 19:43:17 +0100, SHands wrote:

> For those that are in IT - we've probably all see comms cabinets from
> hell, and this is no exception (so before a sub-topic gets going here -
> I'm chiming in with my war story!

The second-worst I've seen was in a server room that I designed - someone else insisted on designing the comms 
cabinets and patch panels.  For a quiet life I let them - I won't make *that* mistake again!  :-)

The building was laid out with a number of CAT5 sockets per desk (3 or 4) and they all terminated in the patch 
panels in the cabinets.  The "designer" put these all in the middle of each cabinet, with telephone sockets 
above, and the Ethernet hubs below.  Then they ordered about a thousand 2-metre patch cables!  The resulting 
rats' nest was almost unmaintainable - the bundles of cable going up and down in each cabinet almost stopped 
the doors closing, and it was impossible to trace any cable without somehow following it through the bundle - 
dreadful mess!  I did at least get them to colour-code the cables by usage, which helped a tad.

The *worst* I've seen was only two cabinets, adjacent.  All of the room-sockets terminated in one cabinet, all 
of the hubs and phone connections were in the other - so every cable traversed between the cabinets, and it 
was *impossible* to trace them!

What I have learned is that patch-cables should be as short as possible, without being tight as a bow-string, 
and I order a lot of 300 and 500mm patch cables, and interleave the types of socket down the cabinet, so going 
from the top you'd have, say, one 24-way telephone strip, two 24-socket patch panels (going to the floors), 
one 24-port Hub, then repeat.  By doing this most of the floor-sockets have a short cable going up or down one 
or two units, no more.  Since seeing the two disasters I had a (small) cabinet to set up for a client, and I 
did it "my" way.  Everyone else from the network people to the telephone engineers to the cable installers 
argued that it was the wrong way to do it, but I insisted and when it was done the result was pretty good, and 
in future I will do it that way again, if I ever have a job doing that.

The other thing is socket numbering.  Installers tend to number the floor-sockets sequentially, which really 
doesn't help with physical location.  75 may be next to 74, or may be at the far end of the building.  I 
insist on numbering the floor- or wall-boxes sequentially, and lettering the sockets in each, so 22B is in the 
same box as 22A but not the same as 23A.  This saves a huge amount of time when patching-up and changing 
wiring later.  It also allows new sockets to be installed in existing boxes and keeping the numbering scheme 
clean, whereas with sequential sockets you can end up with 74, 75 and 123 in the same box...

Cheers,



Cheers,


Howard Winter
St.Albans, England


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