In a message dated 97-05-02 11:22:15 EDT, you write:
> I have a tower question for you if you dont mind. We have just put up a
Rohn
> 25 tower 100 feet that is guyed every 30 feet. We used 1/4 inch cable. I
> would like to know how much tension we need to put on the guy cables. I
> think with 3/16 cable it says to 40% of the cable stringth but with 1/4
inch
> I think that would be way too much........please advise if you dont mind.
Hi, Ernie --
The normal guy tension is 10% of the ultimate breaking strength. For
1/4 inch EHS that has an UBS of 6700 pounds, it would be tensioned at 670
pounds. If your 1/4 inch cable is wire rope of some other grade, then the
tension would be different.
No 25G configuration in the Rohn catalog uses 1/4 inch cable - it's all
3/16. I would suggest using a slightly less figure for final tension, say
550 pounds that is inbetween the two in terms of tension.
I understand from excellent authority that use of 1/4 inch EHS and its
670 pounds of tension is accecptable on the 25G. Apparently the legs will
take the additional compression with no problem. I'll post this to TowerTalk
for additional input.
Now that you know what the tension should be, the $64.00 question is how
do you determine when you've actually got it? While there are a couple of
methods that you could use, by far the fastest, easiest and cheapest is to
use a LOOS guywire tensioner. It'll give pretty accurate readings of 3/16
and 1/4 inch cable, only takes about 10 seconds to take a measurement and
only costs $39.00. It's available from TOWER TECH.
73, Steve K7LXC
TOWER TECH -- professional tower supplies and services for amateurs
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