Larry:
For that length of conduit run, I'd advise against corrugated drain
pipe. The leading end of the cable/snake rope will get caught in the
corrugations along the way. You ought to consider two parallel runs, too,
to accommodate the largish hardline runs.
I'd recommend using PVC conduit - the gray stuff that was meant for
pulling cables through. You didn't say whether this 200 feet was a straight
line or included turns. If turns, then make them with PVC sweeps - NOT
elbows. The sweeps area a gentle radius, rather than an abrupt change in
direction that is difficult to pull - especially hardline - through. You
can buy the sweeps at an electrical supply store, where you would also buy
the PVC conduit and its glue.
No matter whether you've got a straight shot or a path with bends, make
sure you have one or more low spots in the conduit run. Water will drain to
these low spots (and water WILL get into the conduit.) Then simply drill a
few half-inch diameter holes in the underside of the conduit at these low
spots and cover the holes with landscaping fabric (the kind that lets water
drain in only one direction) and tie the fabric in place around the conduit
at the holes with #14 solid wire (it's cheap.)
The final step is to construct a sump well underneath the holes into
which the conduit water will spill. This sump drain is a hole that you
refill with gravel or crushed rocks. Some folks might call this a French
drain. The size of the sump drain hole depends on how many low spots you
have and how much water each drain hole must disperse.
A final bit of advice: When you lay out your cable at one end of the
conduit run, don't lay it out in a long, straight line. If you do, you'll
be pulling the entire length of the cable all the time. Instead, lay out
your cable on the ground at one end of the conduit run in a serpentine
pattern (remember "The Inlaws"?) at right angles to the conduit run so that
you are adding only one S-curve of cable to the pull weight at a time. The
cable will look kind of like this === SSSSSS before you pull, with the top
of one S connected to the bottom of the next one, etc. (The == is the
conduit.)
73 de
Gene Smar AD3F
----- Original Message -----
From: "Larry Boekeloo" <lboekeloo@sbcglobal.net>
To: <towertalk@contesting.com>
Sent: Monday, July 27, 2009 10:45 AM
Subject: [TowerTalk] Cable Runs
My new tower will be 200 feet from the shack. Any ideas what to run the
cables in underground? Pvc? Flexbile black piping?
I'll have four runs of hardline and three runs of rotor cable. Looking for
ideas from the group.
Thanks.
Larry, KN8N
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|