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Hello,<br>
<br>
I recently noticed we had multiple modems offline at Capitol Peak.
Dale & I went to visit Capitol Peak a few days ago to inspect
the situation. This is what we found:<br>
<br>
<a class="moz-txt-link-freetext" href="https://photos.app.goo.gl/KXajGkDGLsW41dQz7">https://photos.app.goo.gl/KXajGkDGLsW41dQz7</a><br>
<br>
It's a little hard to see in the photos, but our cable bus has been
ripped off the tower. When examining the cabinet where the cables
terminate, I found the cables to be wet, and we discovered water
pooling in the bottom of the cabinet:<br>
<br>
<a class="moz-txt-link-freetext" href="https://photos.app.goo.gl/kWwAWs2FvA6ghhC28">https://photos.app.goo.gl/kWwAWs2FvA6ghhC28</a><br>
<br>
So not only are the cables dangling, they're also broken to the
point where we lost communications and are now taking on water.
This was likely caused by ice falling onto the cables, since that
bottom bundle was mounted in such a way that it was protruding
inside the tower, instead of being under the cover of angle iron
like the rest of the horizontal coax nearby. It's hard to pin down
exactly when this happened, but the data I've seen points to Jan
23rd for S3 falling offline.<br>
<br>
There is another cable of ours that had its support removed about
80ft up the tower. It feeds the BawFaw link. The damage was again
along a horizontal run, from the cable ladder to the dish on the
opposite side of the tower from the cable ladder. We typically run
these under the steel members, so I'm not sure what the failure
there was. I wasn't able to take good pictures of the dangling
cable.<br>
<br>
The whole bottom bundle is impacting on the edge of angle iron
whenever the wind blows. This has likely cut through the cables,
although poor weather didn't allow close visual inspection.<br>
<br>
I think this situation calls for some engineering changes in
addressing this and other future deploys:<br>
<br>
1) All horizontal runs must be protected from falling ice, by having
steel members above them.<br>
2) We should evaluate the use of tougher cable that is more
resistant to physical damage.<br>
3) We should evaluate the use of cable that is water-resistant when
it does get breached.<br>
4) We should evaluate the use of drip-loops (removing a section of
jacket) before the cable reaches expensive equipment.<br>
5) We should measure the forces required to remove beam clamps and
establish minimum torque requirements.<br>
6) A camera system may have spotted these cable failures before we
experienced communication outages. Deployment has been approved.<br>
<br>
There is some good info on addressing (3) on this page, thanks to
Dale's research:<br>
<br>
<a class="moz-txt-link-freetext" href="https://www.truecable.com/blogs/cable-academy/into-the-great-outdoors-running-ethernet-cable-outside">https://www.truecable.com/blogs/cable-academy/into-the-great-outdoors-running-ethernet-cable-outside</a><br>
<br>
To address (2) I think we can look at stepping up to CAT6, which is
AWG23 instead of AWG24, and has a larger outer diameter. The
presence of a spline will also make the cable stronger.<br>
<br>
This leaves us with a cushion problem, since our cushions are only
designed for 1/4" cable and CAT6 is thicker than that. It seems we
have gotten exceedingly lucky here! Valmont has just recently
released a new cushion design that accepts 7 runs of 4mm-9mm cable!
The part # is BCU158M7.<br>
<br>
<img src="cid:part1.294F9ECA.8624B745@bartk.us"><br>
<br>
We also need to make sure these new cable selections will be
compatible with our current-spec EZ-RJ45 ends.<br>
<br>
I'm going to send a separate VOTE email to approve the purchasing of
samples of this new hardware, so I can verify it will all work
together. Let's use this thread to discuss the problems, and if
anyone has other/better solutions please share here.<br>
<br>
--Bart<br>
<br>
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