Sand around any conduit/pipe in rocky soil is a good practice. At my WA
QTH any holes would let water in even if the conduit was barely covered
with dirt. I tried simultaneous pull & glue once and wouldn't do that
again. It's just to messy and dirty and risks gluing the cable to the
conduit. I put in 2" conduit for power and 3" or 4" for coax and
control lines. Code says they need to be at different depths if in the
same trench, but....
You might consider fiberglass/plastic enclosures rather than steel - no
rust and much easier to punch or drill for 4" conduit. check McMaster
and ebay. They can't be too big considering junctions, service loops,
surge arrestors for rotators & steppIRs, grounding plates, etc.
Something not mentioned so far in these posts is the ability to use
continuous run conduit. Your local underground horizontal drilling
contractor would probably cut off a chunk from his giant spool and might
have some short ends for free. I was left several pieces 30 to 60' long
after a new primary line was run to the new transformer and new service
runs to generator, house, and shop. Regular couplings work sch 40 or
80. Unfortunately my scraps are sch 80 which takes 3 men and a gorilla
to straighten on any day less than 80 deg. Drilling and continuous
conduit has the advantage of a smooth interior and going around and
under stuff like driveways, but is not cheap.
And one more input - sweeps are available in various bend radii for 2"
and larger conduit. I've seen two radius sizes at HD, and electrical
suppliers carry larger radii. IIRC Puget Sound Energy wants 48" radius
on the service entrance ends and limits how many of these (3?) are
permitted in a run. Sometimes sch 80 is required for exiting from
underground for extra strength to the box/meter. Again, I've seen random
sch 80 sweeps at HD which they deny they stock.
Grant KZ1W
On 2/25/2013 8:35 PM, Steve K7AWB wrote:
This April, I will install my conduit and pull the cables to the
existing towers. From the shack
wall, its about 100 feet to Tower #1 and an additional 130 feet to
Tower #2.
I live on 20 acres.
The cables to Tower #1 will terminate in a steel enclosure at the
bottom of
that tower. Also, the cables to the far Tower #2 will terminate in a
steel
enclosure at the base of Tower #1 and then continue to Tower #2 in
their conduit.
I probably will use three of the 4" PVC conduits for all the cables
to get to Tower #1. One will contain the cables for Tower #1 use;
another
for Tower #2 use; and the third for future projects in the back field.
Then
one additional conduit goes from Tower #1 to Tower #2. Ands one
additional goes in another
direction also from Tower #1 for future area in the back field.
I figure to glue and bury the conduit in the ground first and put sand,
dirt, & rock on top of it so pulling cables will not pull the conduit
out of the
ground rather that gluing each section, one at a time, around the cables.
Is burying the conduit before pulling a good idea like I suggest?
After all,
once it is buried, it is impossible to remove it economically. I will
use
sand to create a smooth bottom for the conduits to rest on and then cover
them with dirt. Its all fractured basalt out there, but the back hoe
that
was used managed to make the trenches. The trenches are about 24" deep or
so.
I know this has been discussed before, but I still have not decided on
drilling or not a few water holes in the bottom every so often, or at
least
at the lowest spots, to drain water from condensation. Holes bring bugs
which may or may not matter. I don't want a small hole to become an
enlarged entrance hole for a Vole which I have out there.
Any suggestions would be welcome.
Steve Sala
K7AWB
DN17es
Nine Mile Falls, WA
_______________________________________________
_______________________________________________
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
|