I was surprised at this thread! I hadn't been aware of any previous threads
related to the use of Loos gauges nor did I know they were not meant for EHS
cable!
Someone had said "when you get up to 10% tension they read roughly right"
(paraphrasing but I believe the essence is correct) ... well that isn't so!
I JUST finished running the cables today for my new installation... 148'
rotating tower with 6 large monobanders on it ... Looks REALLY sweet ...
anyway the guy doing the tower work, Benny out of Tenn. (great guy - great
work - great prices) brought a Penn-Tech gauge with. It IS designed for EHS
... I used it to set the top guy which is 5/16" (EHS and 1/2 philly) ... so
I took his gauge and compared it to my Loos model B (and to his Loos PT2)
... the Loos B read ~630# on the 1/4" EHS guys (middle and bottom sets) ...
the PT2 read 680# ... the PT ... it read 400! 4 0 0 !!!
In my humble opinion that is scary far from where I THOUGHT it was - like
more than 50% of the actual rating shy of the desired tension spot (660#
with ~ 68degrees).
WOW. I was blown away. All the 7 years I had my loaded tower up in AZ I had
the same tension - so it too was under tensioned.
So I'm going to adjust the bottom set of guys using the PT and then once it
is set correctly at 660# I will then compare it to the LOOS and I'll then
have a comparison point I can pass along to anyone using the Loos (model B)
Gary
K9RX
[I've been working on this project for 18 months - poured concrete in
December of last year ... FINALLY have it all up. I'm still not done as the
crane got canceled for our scheduled time and I was concerned it would get
pushed out too far so I asked if they'd do Saturday - w/o OT since they
canceled it - they said YES and we had 9 hours of listening to that diesel
engine yesterday ... so because of the rush I still have to install the
terminal boxes at the base of the 2 towers and wire everything up (5 miles
of control wire) but I was able today to just put a power supply at the base
of the antenna and use my SARK to check and all 6 antennas - SWEET!
Including a modified Optibeam OB4-40 that is near perfect]
-----Original Message-----
From: K7LXC@aol.com
Sent: Saturday, October 22, 2016 8:27 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Guy Tensioning
The calibration chart that comes with the instrument is correct only
for the 19-strand wire rope it was designed for, which is what they use for
sailboat rigging. The stiffness of the cable determines the reading as
much as does the tension. The chart that comes with the gauge is WAY off
and
totally useless for EHS guy cable. I'm sure it would be just as far off,
if not more so, with phillystran.
With the two pieces tied together, they both have the same tension, so
the tension reading on the wire rope has to be the same as the tension on
the EHS, thus allowing me to make up an accurate chart for 3/16 EHS. That
same procedure would work equally well with phillystran; I would make up a
separate chart for each.
Howdy --
Here's my 2 cents worth again. I conducted the same test only I also
had a segment of HPTG4000 inline and you proved my point, which is that
they
all read the same. As a wire rope has tension increased on it, it becomes
more rod-like regardless of type of material. So what do your charts say?
Are they similar or what? Are you dealing with a couple of percent or
something else? Inquiring minds want to know.
BTW the Loos PT-2 will only measure HPTG4000 due to the size of the
jacket but it does fine on it.
Cheers,
Steve K7LXC
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