Can't help you on the mounting issues but I would try to keep the electrical
part simple. Use 12V for everything. One source, one set of stuff to
maintain and no code issues for low voltage lines running up the tower. If a
wire breaks later, there is no problem with a possibly hot high voltage line
lying around.
Make sure that you have enough air circulation/ventilation in the NEMA box
to keep the 12V PS cool. You can get boxes with a fan and filter for this
purpose or roll your own which would probably be much less expensive. Use a
12V fan, of course.
Les W2LK
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Doug Rehman
Sent: Tuesday, July 05, 2005 12:06 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Obstruction Lighting
Due to my proximity to a small airport, the FAA is requiring obstruction
lighting (L-810 light or lights) on my tower; painting is not required
though. The tower will be a Tri-Ex LM-354HDSP 54' crank-up with 15' of mast
out the top.
My first decision is where to mount the light(s). I was planning on a
VHF/UHF vertical on the top of the mast. If I do this, then I'm going to
need two lights since the light couldn't sit on the top of the mast. To cut
the lighting cost in half, I will probably make a sidearm for the VHF/UHF
vertical to mount on pointed downward, thus allowing the light to sit on the
top of the mast.
The next decision isn't quite as easy to make. I can use a standard 110 VAC
light that costs about $120 or a 12 VDC light that costs $223 (Dialight
model 860-1R03-001 from www.unimar.com). Either option only requires a
couple of amps.
I will have mast mounted preamps for 6m, 2m, and 70cm mounted at the top of
the tower, so I need 12 VDC there anyway. I could run 110 VAC to a NEMA box
with a 12 VDC power supply in it to feed the preamps and use the 110 VAC to
feed a standard L-810 light. A heavy outdoor extension cord, or stranded
THHN, encased in flexible conduit would be used to run the 110 VAC to the
top. The tower will already have 110 VAC at the base to run the winch.
Alternatively, I could use the more expensive 12 VDC L-810 light and just
run 12 VDC to the tower top for everything; running the preamps and light
from a trickle charged battery would provide for emergency power.
I'm leaning strongly towards the last choice (all 12 VDC on the tower), but
looking for input from the collective wisdom and experience of the group
before committing.
Thanks,
Doug
K4DDR
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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