Re: [RE-wrenches] pole mounts
I've not personally seen any pole mount pipes that were bent or broken. Has anyone seen this? How common is it? What sort of damage to pole mount arrays is common? At 05:25 PM 7/26/2011, you wrote: I can confirm that quite a bit of water builds up inside the pipe. A few times on rewiring old systems, we used self tapping screws to attach conduit and combiner boxes to the existing pole, and we've had water start running out the hole when it was close to the ground. This was in a dry climate (New Mexico) This was with a rack that didn't cap the pole, but I was still surprised how much water was in there. (gallons) Filling with concrete does seem to be a good idea, but I'll point out its not as easy as it sounds. The concrete just pours out the bottom into the footing, as you keep filling it from the top. Pouring in a foot of gravel in the bottom first would help, or filling the pipe after the footing dried some would do it too. No free lunch, R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 2:08 PM, Dave Palumbo wrote: Roy, I have heard that the small amount of water from condensation will be absorbed by the concrete itself. Don't know for an absolute fact that this is true though. Dave -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Roy Rakobitsch Sent: Tuesday, July 26, 2011 3:17 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer® NABCEP Certified Solar PV Installer® NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldnât say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org Drake Chamberlin ATHENS ELECTRIC OH License 44810 CO license 3773 NABCEP Certified PV ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re
Re: [RE-wrenches] pole mounts
Drake, I have never seen significant damage due to rust, but ours is a dry climate. But we had a real scary pole issue a few years ago. In 1997, just starting out and before I was licensed, we hired another PV pro to install a SW4024 GTWB system for us. He used a Romex connector for strain relief on some USE-2 array wiring into an array combiner box. The PV input conductors were direct-burial USE, not in conduit and without a bonding conductor between the array and the BOS. There was a #6 bare from the combiner to a ground rod at the array. The Romex connector pinched through the insulation on one array conductor, causing a low-voltage ground fault. This leakage couldn't be detected from the BOS in the house. The ground #6 carried this to the rod for maybe ten years. It finally failed from electrolytic corrosion and weather exposure, and once it did the 6" sch. 40 array pole had the electrolytic reaction and began aggressively rusting out from the inside. We discovered bubbling of the steel around the base of the pole and the tech that day stuck a screwdriver right through the pole at the base. Needless to say, that array was taken down that day. The customer poured a base up a foot around the pole, and filled it with rebar and concrete, and it's good. Allan Allan Sindelar al...@positiveenergysolar.com NABCEP Certified Photovoltaic Installer NABCEP Certified Technical Sales Professional New Mexico EE98J Journeyman Electrician Positive Energy, Inc. 3201 Calle Marie Santa Fe, New Mexico 87507 505 424-1112 www.positiveenergysolar.com On 7/27/2011 3:40 PM, Drake wrote: I've not personally seen any pole mount pipes that were bent or broken. Has anyone seen this? How common is it? What sort of damage to pole mount arrays is common? At 05:25 PM 7/26/2011, you wrote: I can confirm that quite a bit of water builds up inside the pipe. A few times on rewiring old systems, we used self tapping screws to attach conduit and combiner boxes to the existing pole, and we've had water start running out the hole when it was close to the ground. This was in a dry climate (New Mexico) This was with a rack that didn't cap the pole, but I was still surprised how much water was in there. (gallons) Filling with concrete does seem to be a good idea, but I'll point out its not as easy as it sounds. The concrete just pours out the bottom into the footing, as you keep filling it from the top. Pouring in a foot of gravel in the bottom first would help, or filling the pipe after the footing dried some would do it too. No free lunch, R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 2:08 PM, Dave Palumbo wrote: Roy, I have heard that the small amount of water from condensation will be absorbed by the concrete itself. Don't know for an absolute fact that this is true though. Dave -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [ mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Roy Rakobitsch Sent: Tuesday, July 26, 2011 3:17 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer NABCEP Certified Solar PV Installer NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade
Re: [RE-wrenches] pole mounts
We have more than 70 pole mounted systems, including one of my own that is 16 years old, and I have not seen any problems. Our oldest pole mount installation is 20 years old and at least visibly, is not showing any signs of wear and tear.I inspected it last time I was there, less than a year ago. We have had winds up to 80 mph that I can remember since we have been installing.We do not fill the poles with concrete, but always use capped pole mounts, that is, those that cover the open end of the pipe on top. Just reporting my experience, not advocating for anything.. Daryl DeJoy NABCEP Certified PV installer Penobscot Solar Design I've not personally seen any pole mount pipes that were bent or broken. Has anyone seen this? How common is it? What sort of damage to pole mount arrays is common? At 05:25 PM 7/26/2011, you wrote: I can confirm that quite a bit of water builds up inside the pipe. A few times on rewiring old systems, we used self tapping screws to attach conduit and combiner boxes to the existing pole, and we've had water start running out the hole when it was close to the ground. This was in a dry climate (New Mexico) This was with a rack that didn't cap the pole, but I was still surprised how much water was in there. (gallons) Filling with concrete does seem to be a good idea, but I'll point out its not as easy as it sounds. The concrete just pours out the bottom into the footing, as you keep filling it from the top. Pouring in a foot of gravel in the bottom first would help, or filling the pipe after the footing dried some would do it too. No free lunch, R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 2:08 PM, Dave Palumbo wrote: Roy, I have heard that the small amount of water from condensation will be absorbed by the concrete itself. Don't know for an absolute fact that this is true though. Dave -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Roy Rakobitsch Sent: Tuesday, July 26, 2011 3:17 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer® NABCEP Certified Solar PV Installer® NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldnât say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out
Re: [RE-wrenches] pole mounts
I had a customer ram a vehicle into a pole mounted tracker at about 10 mph. It bent the tilt actuator pretty good, but the 6 pole and footing were unscathed. Once I found a pole mount listing at a 10 degree angle, turns out the DIYers hadn't set it in concrete. Another situation we had 6 poles about 12 ft out of the ground, and in high winds they rocked back and forth a few inches. We added guy cables and anchors, and all is well. Biggest problem I've seen is not bringing the concrete up to ground level. Dirt against the pipe long term will corrode the pipe significantly right at the point of highest stress. Ray On 7/27/2011 3:40 PM, Drake wrote: I've not personally seen any pole mount pipes that were bent or broken. Has anyone seen this? How common is it? What sort of damage to pole mount arrays is common? At 05:25 PM 7/26/2011, you wrote: I can confirm that quite a bit of water builds up inside the pipe. A few times on rewiring old systems, we used self tapping screws to attach conduit and combiner boxes to the existing pole, and we've had water start running out the hole when it was close to the ground. This was in a dry climate (New Mexico) This was with a rack that didn't cap the pole, but I was still surprised how much water was in there. (gallons) Filling with concrete does seem to be a good idea, but I'll point out its not as easy as it sounds. The concrete just pours out the bottom into the footing, as you keep filling it from the top. Pouring in a foot of gravel in the bottom first would help, or filling the pipe after the footing dried some would do it too. No free lunch, R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 2:08 PM, Dave Palumbo wrote: Roy, I have heard that the small amount of water from condensation will be absorbed by the concrete itself. Don't know for an absolute fact that this is true though. Dave -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Roy Rakobitsch Sent: Tuesday, July 26, 2011 3:17 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer® NABCEP Certified Solar PV Installer® NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org http://www.windsine.org/ On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldnâEUR^(TM)t say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm http://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org http://www.members.re-wrenches.org/ ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm http://www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org http://www.members.re-wrenches.org/ ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches
Re: [RE-wrenches] pole mounts
I have run into several 6” sched-40 poles that were “adapted” to 8” for a tracker install. One had bent in the wind. This one got replaced. Another was TRI-braced and custom field engineered modified [can you spell monkey rigged] with the equivalent of a 30 gallon barrel of concrete below frost line at each on the 3 braces and is pretty happy today, it has seen some seriously high 3 second wind blasts. Dana Orzel Great Solar Works, Inc E - d...@solarwork.com V - 970.626.5253 F - 970.626.4140 C - 970.209.4076 web - www.solarwork.com Responsible Technologies for Responsible People since 1988 Do not ever believe anything, but seriously trust through action. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Wednesday, July 27, 2011 4:49 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I had a customer ram a vehicle into a pole mounted tracker at about 10 mph. It bent the tilt actuator pretty good, but the 6 pole and footing were unscathed. Once I found a pole mount listing at a 10 degree angle, turns out the DIYers hadn't set it in concrete. Another situation we had 6 poles about 12 ft out of the ground, and in high winds they rocked back and forth a few inches. We added guy cables and anchors, and all is well. Biggest problem I've seen is not bringing the concrete up to ground level. Dirt against the pipe long term will corrode the pipe significantly right at the point of highest stress. Ray On 7/27/2011 3:40 PM, Drake wrote: I've not personally seen any pole mount pipes that were bent or broken. Has anyone seen this? How common is it? What sort of damage to pole mount arrays is common? At 05:25 PM 7/26/2011, you wrote: I can confirm that quite a bit of water builds up inside the pipe. A few times on rewiring old systems, we used self tapping screws to attach conduit and combiner boxes to the existing pole, and we've had water start running out the hole when it was close to the ground. This was in a dry climate (New Mexico) This was with a rack that didn't cap the pole, but I was still surprised how much water was in there. (gallons) Filling with concrete does seem to be a good idea, but I'll point out its not as easy as it sounds. The concrete just pours out the bottom into the footing, as you keep filling it from the top. Pouring in a foot of gravel in the bottom first would help, or filling the pipe after the footing dried some would do it too. No free lunch, R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 2:08 PM, Dave Palumbo wrote: Roy, I have heard that the small amount of water from condensation will be absorbed by the concrete itself. Don't know for an absolute fact that this is true though. Dave -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [ mailto:re-wrenches-boun...@lists.re-wrenches.org mailto:re-wrenches-boun...@lists.re-wrenches.org ] On Behalf Of Roy Rakobitsch Sent: Tuesday, July 26, 2011 3:17 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer® NABCEP Certified Solar PV Installer® NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org http://www.windsine.org/ On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldn’t say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [ mailto:re-wrenches-boun...@lists.re-wrenches.org mailto:re-wrenches-boun...@lists.re-wrenches.org ] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org
Re: [RE-wrenches] pole mounts
We did a repair on a DIY tracker install that had broken in high wind. Turned out he had used steel tubing instead of schedule 40 steel. The tubing buckled just where it came out of the concrete. One module on the corner of the tracker was shattered and the rack itself was both bent and knocked out of square. It was a Y2K era install so it survived for 9 years before the wind got it. Nathan Jones Power Source Solar Springfield, Mo 417-827-0738 On Wed Jul 27th, 2011 6:31 PM CDT Dana wrote: I have run into several 6” sched-40 poles that were “adapted” to 8” for a tracker install. One had bent in the wind. This one got replaced. Another was TRI-braced and custom field engineered modified [can you spell monkey rigged] with the equivalent of a 30 gallon barrel of concrete below frost line at each on the 3 braces and is pretty happy today, it has seen some seriously high 3 second wind blasts. Dana Orzel Great Solar Works, Inc E - d...@solarwork.com V - 970.626.5253 F - 970.626.4140 C - 970.209.4076 web - www.solarwork.com Responsible Technologies for Responsible People since 1988 Do not ever believe anything, but seriously trust through action. From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Ray Walters Sent: Wednesday, July 27, 2011 4:49 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I had a customer ram a vehicle into a pole mounted tracker at about 10 mph. It bent the tilt actuator pretty good, but the 6 pole and footing were unscathed. Once I found a pole mount listing at a 10 degree angle, turns out the DIYers hadn't set it in concrete. Another situation we had 6 poles about 12 ft out of the ground, and in high winds they rocked back and forth a few inches. We added guy cables and anchors, and all is well. Biggest problem I've seen is not bringing the concrete up to ground level. Dirt against the pipe long term will corrode the pipe significantly right at the point of highest stress. Ray On 7/27/2011 3:40 PM, Drake wrote: I've not personally seen any pole mount pipes that were bent or broken. Has anyone seen this? How common is it? What sort of damage to pole mount arrays is common? At 05:25 PM 7/26/2011, you wrote: I can confirm that quite a bit of water builds up inside the pipe. A few times on rewiring old systems, we used self tapping screws to attach conduit and combiner boxes to the existing pole, and we've had water start running out the hole when it was close to the ground. This was in a dry climate (New Mexico) This was with a rack that didn't cap the pole, but I was still surprised how much water was in there. (gallons) Filling with concrete does seem to be a good idea, but I'll point out its not as easy as it sounds. The concrete just pours out the bottom into the footing, as you keep filling it from the top. Pouring in a foot of gravel in the bottom first would help, or filling the pipe after the footing dried some would do it too. No free lunch, R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 2:08 PM, Dave Palumbo wrote: Roy, I have heard that the small amount of water from condensation will be absorbed by the concrete itself. Don't know for an absolute fact that this is true though. Dave -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [ mailto:re-wrenches-boun...@lists.re-wrenches.org mailto:re-wrenches-boun...@lists.re-wrenches.org ] On Behalf Of Roy Rakobitsch Sent: Tuesday, July 26, 2011 3:17 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer® NABCEP Certified Solar PV Installer® NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org http://www.windsine.org/ On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldn’t say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [ mailto:re-wrenches-boun...@lists.re-wrenches.org mailto:re-wrenches-boun...@lists.re-wrenches.org ] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches
Re: [RE-wrenches] pole mounts
Todd, Of course putting concrete inside a pipe will make it stronger, but not by as much as you might think. Concrete is strong in compression and has very little strength in tension. The pole is subjected to bending stress and thus has tension on one side and compression on the other. Even with concrete in the pipe, the tension stress is almost entirely carried by the steel. Failure by buckling occurs on the compression side of the pole so the concrete will help in that regard. But repeated loading to more than 50% of maximum can ultimately lead to fatigue failure (crack propagation) that may take many years to show up. Kent Osterberg Blue Mountain Solar toddc...@finestplanet.com wrote: Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] pole mounts
Colleagues: See photos at http://millersolar.com/case_studies/Wind_damage/wind_damage.html William Miller At 02:40 PM 7/27/2011, you wrote: I've not personally seen any pole mount pipes that were bent or broken. Has anyone seen this? How common is it? What sort of damage to pole mount arrays is common? ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] pole mounts
It definitely stiffens the pole, and prevents water from rusting it out from the inside. While I might use the stiffening effect to get a couple of extra feet out of the ground, I wouldn't start downsizing your poles because you poured concrete in them. I think it would be fair to compare the effect of adding concrete to going to SCH 80 pipe. Unfortunately, I don't have any good structural analysis to back that up, but if we have the extra concrete, we try to fill the pole. One of these days if I get a research grant, I'll do some deflection tests to try and better quantify this. R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 12:49 PM, toddc...@finestplanet.com wrote: Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] pole mounts
Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldn’t say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] pole mounts
I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer® NABCEP Certified Solar PV Installer® NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldnât say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] pole mounts
Todd: Fact, according to Jeff Randall of DPW. The concrete need only come a few feet above ground level as that is the point the pole would bend. Wm At 11:49 AM 7/26/2011, you wrote: Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1390 / Virus Database: 1518/3788 - Release Date: 07/25/11 William Miller Miller Solar Voice :805-438-5600 email: will...@millersolar.com http://millersolar.com License No. C-10-773985 ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] pole mounts
I can confirm that quite a bit of water builds up inside the pipe. A few times on rewiring old systems, we used self tapping screws to attach conduit and combiner boxes to the existing pole, and we've had water start running out the hole when it was close to the ground. This was in a dry climate (New Mexico) This was with a rack that didn't cap the pole, but I was still surprised how much water was in there. (gallons) Filling with concrete does seem to be a good idea, but I'll point out its not as easy as it sounds. The concrete just pours out the bottom into the footing, as you keep filling it from the top. Pouring in a foot of gravel in the bottom first would help, or filling the pipe after the footing dried some would do it too. No free lunch, R. Walters r...@solarray.com Solar Engineer On Jul 26, 2011, at 2:08 PM, Dave Palumbo wrote: Roy, I have heard that the small amount of water from condensation will be absorbed by the concrete itself. Don't know for an absolute fact that this is true though. Dave -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Roy Rakobitsch Sent: Tuesday, July 26, 2011 3:17 PM To: RE-wrenches Subject: Re: [RE-wrenches] pole mounts I would think that adding concrete partially up the pole would cause water and condensation to collect near the bottom and not drain properly. This could possibly lead to freezing and the pipe being blown out or damaged, even if the top is completely capped. I would think that you should either completely fill the pipe, or leave it empty with a good layer of gravel at the bottom to allow it to drain properly. I also have no studies to back this up, but it was just a thought. Roy Rakobitsch NABCEP Certified Small Wind Installer® NABCEP Certified Solar PV Installer® NYSERDA eligible Small Wind installer Wind/PV Design Engineer Windsine Inc. 631-514-4166 www.windsine.org On Tue, July 26, 2011 3:05 pm, Dave Palumbo wrote: Todd, We add concrete inside of our steel pipe masts, up to grade level, in the interest of having more weight below ground level. I wouldn’t say that it made the pipe stronger (that better be strong enough as is) but more weight down low will help keep it rooted in a big wind event. Dave From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 2:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] pole mounts
Concrete, even when it's cured enough to be hard is still very high in water content. Concrete exposed to open air won't cure/dry completely for decades. This is why the NEC now recognizes the Ufer ground for the low impedance connection that it offers for grounding properties. Unfortunately the high moisture content in cured concrete inside a pipe will corrode just as much as it will an unprotected Ufer ground rod embeded in concrete. I have also seen heavy condensation on the outside of 8 tracker pipes in cooler temperatures until it warms above the dew point. Jim Duncan North Texas Renewable Energy NABCEP Certified Solar PV Installer No.031310-57 TECL 27398 nt...@1scom.net 817.917.0527 www.ntrei.com -Original Message- From: re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org]On Behalf Of toddc...@finestplanet.com Sent: Tuesday, July 26, 2011 1:50 PM To: RE-wrenches Subject: [RE-wrenches] pole mounts Wrenches, Fact or fiction: Adding concrete to the inside of a pole mount pipe makes it stronger. Thanks, Todd Sent from Finest Planet WebMail. attachment: North Texas Renewable Energy Inc.vcf___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Pole Mounts - Frost/Conduit Ledge
I have done this 18 to 24 below grade conduit and our frost is 4 to 5 feet I have seen it freeze to 11 feet, I have not had a problem. I have in clay areas seen telephone poles pushed out of the ground. dt From: Glenn Burt glenn.b...@glbcc.com To: RE-wrenches re-wrenches@lists.re-wrenches.org Sent: Sat, April 16, 2011 10:30:48 AM Subject: Re: [RE-wrenches] Pole Mounts - Frost/Conduit Ledge 1) When we use this option, we bring the PVC conduit into the Sonotube below frost level. 2) We had a similar situation after consulting with an engineer, widened the form at the top, just below the ground according to his calculations – turned out almost to be a patio. Then they were buried. So I recommend finding an engineer to evaluate the TPM requirements and adapt a foundation to an equivalent. Good Luck! Glenn Burt From:re-wrenches-boun...@lists.re-wrenches.org [mailto:re-wrenches-boun...@lists.re-wrenches.org] On Behalf Of Rich Nicol Sent: Saturday, April 16, 2011 10:55 AM To: re-wrenches@lists.re-wrenches.org Subject: [RE-wrenches] Pole Mounts - Frost/Conduit Ledge Hi RE-Wrenches 1. When installing pole mounts I have been running conduit into the side of the foundation and up the pole prior to pouring concrete. The conduit enters the foundation ~ 18” to 24” below grade level. We live in an area where frost depths are around 48” deep. I have been told by folks in the construction industry that frost will not be problem with the conduit entry but I remain concerned that the conduit may be lifted, while the foundation which runs to below the frost depth, remains stationary thereby breaking the conduit. Any insights? 2. Secondly, does anyone have experience with ledge in respect to pole mounts. I know the answer is to consult an engineer, but I thought I would bring it up to the experienced folks in the trade first. I have two mounts scheduled for this spring where I expect to hit ledge. The first is a TPM with six 230 watt modules and the second is with eight 230 watt modules. I’m expecting ledge to be relatively close to grade level, perhaps around 12 to 24” deep. Ledge in these locations is solid (generally granite, sometimes gneiss or basalt). My initial thought is to form a larger rectangular foundation with pins drilled at 45 deg angles into the ledge and tied to the reinforcing within the foundation. A wide base on the pole would then be bolted to the foundation. Any recommendations? Thanks Rich___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
Re: [RE-wrenches] Pole Mounts - Frost/Conduit Ledge
Hi Rich; 1) I never had a problem with conduit and frost heave, but then again, I haven't dug up all my work after 10 years either. 2) We did a mount exactly as you described, large slab with rebar into the rock at 45s, and bolt the pole to j bolts in the concrete. I can share our design drawings if you like. We included gussets on the base plate, and the slab is large enough to overcome the tipping moment of the wind load. Definitely want to keep the pole as short as possible on these. You may want to consider a ballasted design. We've done a few off grid versions that used the batteries as ballast. R. Walters r...@solarray.com Solar Engineer On Apr 16, 2011, at 8:55 AM, Rich Nicol wrote: Hi RE-Wrenches 1. When installing pole mounts I have been running conduit into the side of the foundation and up the pole prior to pouring concrete. The conduit enters the foundation ~ 18” to 24” below grade level. We live in an area where frost depths are around 48” deep. I have been told by folks in the construction industry that frost will not be problem with the conduit entry but I remain concerned that the conduit may be lifted, while the foundation which runs to below the frost depth, remains stationary thereby breaking the conduit. Any insights? 2. Secondly, does anyone have experience with ledge in respect to pole mounts. I know the answer is to consult an engineer, but I thought I would bring it up to the experienced folks in the trade first. I have two mounts scheduled for this spring where I expect to hit ledge. The first is a TPM with six 230 watt modules and the second is with eight 230 watt modules. I’m expecting ledge to be relatively close to grade level, perhaps around 12 to 24” deep. Ledge in these locations is solid (generally granite, sometimes gneiss or basalt). My initial thought is to form a larger rectangular foundation with pins drilled at 45 deg angles into the ledge and tied to the reinforcing within the foundation. A wide base on the pole would then be bolted to the foundation. Any recommendations? Thanks Rich ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org ___ List sponsored by Home Power magazine List Address: RE-wrenches@lists.re-wrenches.org Options settings: http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org List rules etiquette: www.re-wrenches.org/etiquette.htm Check out participant bios: www.members.re-wrenches.org
