George, Our expert said that lightning surge likes to follow a straight line and that it would not follow a path like the one in the picture, and effectively “back up”. That is similar to how we do it now, except we make the path more of a straight line… instead of having them all at the same position, the first clamp would be say 4 ft away on the top wire, then the 2nd clamp at 3 ft. away, etc. etc. keeping the path much more straight.
I probably mis-understood what I thought I heard about cad-welding to the guy wire though. It was two years ago we had him come in. Paul From: Af [mailto:[email protected]] On Behalf Of George Skorup (Cyber Broadcasting) Sent: Monday, March 23, 2015 11:30 PM To: [email protected] Subject: Re: [AFMUG] Cad welding expert advice needed :) Paul, Here's the example I was looking for. Check out these two pictures. http://www.r56audits.com/wp-content/themes/r56-child/images/tower-large-img6.jpg http://www.r56audits.com/wp-content/themes/r56-child/images/tower-large-img7.jpg One of the reasons you want this is to limit how much anchor material loss you get. It may take years or even decades for the anchor rod to completely corrode, but that means the tower falls over. I've seen this happen at two towers over the years. And neither of them were grounded properly like this. On 3/23/2015 8:46 PM, Paul McCall wrote: Well phooey.. a lot of this contradicts what my well-pay grounding expert, and well-recommended from to big EOCs in my area has to say about it. At least the part of welding to the tower. I AM glad I asked and could see certainly see how a guy wire under tension could “break / cut” while cad-welding. So, in a typical guyed scenario (let’s say 4 levels of guys for example), I have turnbuckles attached to the guy “Flange/gusset – whatever you want to call it & deadends connecting the guy wires to the turnbuckles, the turnbuckles going through a hole in the gussets would not seem to be a good connection, so attaching the ground wire just to the gusset I think would be “weak” grounding. If the guy wires were to continue past the deadend, pass the turnbuckles, then it could connect to the plate, but how, if the cadwelding will burn through the guy wire. Paul From: Af [mailto:[email protected]] On Behalf Of George Skorup (Cyber Broadcasting) Sent: Monday, March 23, 2015 8:42 PM To: Subject: Re: [AFMUG] Cad welding expert advice needed :) Nope, not close enough to get hit. Just wind vibration as far as I can tell. Always broken near the wire clamps. If the ground wire was stranded and could flex, then it probably wouldn't break. At least that's my theory. Can't hurt to try. On 3/23/2015 7:25 PM, Erich Kaiser wrote: Why are they breaking? Is the farmer hitting them? Erich Kaiser North Central Tower [email protected]<mailto:[email protected]> Office: 630-621-4804 Cell: 630-777-9291 On Mon, Mar 23, 2015 at 7:06 PM, George Skorup (Cyber Broadcasting) <[email protected]<mailto:[email protected]>> wrote: I have a problem site that we lose gear at every year (360' FM site). All of your guy wires are supposed to be bonded at the guy points (and the actual wires, not the pre-forms). And they're all broken every year. I've requested year after year that they do NOT use solid copper wire to tie all of the guys together. Instead, use like #6 or #4 stranded. But no, it doesn't happen. BTW, cadwelding is supposed to be done with nickel plated copper wire. And no, I would not attempt to cadweld to a Rohn 25 or 45 leg. The tubular legs are too thin and you'll burn through them. If you're using a base plate, that's probably OK. On 3/23/2015 4:01 PM, Ken Hohhof wrote: I was not aware you could cadweld to guy wires. From: Paul McCall<mailto:[email protected]> Sent: Monday, March 23, 2015 3:40 PM To: [email protected]<mailto:[email protected]> Subject: [AFMUG] Cad welding expert advice needed :) First foray into cad welding… actually my logistics guy is digging into it. We basically need to do 3 types of welding for towers. 1) Welding copper ground cable to the guy 3/16”, ¼” and 5/16” wires 2) Welding copper ground cable to ground rods 5/8” 3) Welding copper ground cable to Rohn 25G and 45G tower piece. Looking at lots of models, pieces parts. Anybody have some practical suggestions on pieces parts, vendors etc? Thanks! Paul McCall, Pres. PDMNet / Florida Broadband 658 Old Dixie Highway Vero Beach, FL 32962 772-564-6800<tel:772-564-6800> office 772-473-0352<tel:772-473-0352> cell www.pdmnet.com<http://www.pdmnet.com/> [email protected]<mailto:[email protected]>
