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  • lkstaack
    Solar Fanatic
    • Nov 2014
    • 140

    New Ground Mount Installation in San Diego

    After three months of post-contract waiting, I’m finally getting my 5.88 kilowatt ground mount photovoltaic system installed this week, starting on Monday. Since there aren't many ground mount systems on this board, I thought I’d document it. This is what I am expecting to have installed:

    • 21 LG 280 Mono X panels
    • Solar Edge SE600 inverter
    • 21 Solar Edge P300 optimizers

    I’m surprised at how little I know about the installation; I am trusting that my contracted company knows what they are doing. I know it will be mounted in my back yard anywhere from 40’ to 60’ down a steep slope. However, there is much I don’t know about the install because I was told that “the designer would work out those details”. So, the install will be as much a surprise to me as anyone. I don’t know:

    • Estimated time for installation
    • Type of racking
    • Type of footing
    • Orientation and tilt (the hill faces 215* and the slope is 30*, so I assume that will be used)
    • Panel configuration (I assume 7x3)
    • Exact location of panels (I’ll get partial summer morning shading if its less than 50’ down the hill)
    • Where the inverter will be located (the sales rep said they often mount them under the ground mount rack and run AC (along with CAT 5) to the house)
    • Where in my backyard the trench will be run and which part of my sidewalk will be cut
    • How the trench is going to be dug down my slope (I’ll be amazed if they can get a machine down there, and my ground is so hard and rocky that you really need a jackhammer)

    I’m paying $4.65/watt for this system. While that is more than many pay, I’m paying a premium for a system that will require a lot more labor to install (and I can defer re-roofing my house for five years). It was the second cheapest among the estimates for three roof mounts and two ground mounts. Both companies that offered ground mounts indicated up front that they propose their best price while the other three hinted that their price was negotiable.

    I selected a small but reputable electrical company to do my solar that at least two members of this forum have used. They have been providing residential and commercial electrical services for 30 years and solar for 10, so they should still be in business if the industry slumps. They were unlike most companies in that their sales rep wasn't a young man; he was an older gentleman who knew more about solar than everyone else, but lacked polish. He almost didn’t get the job by pissing off my wife (heaven help the man who treats my wife like the junior partner).

    I received five proposals when I was shopping. I was amazed at how single-minded many companies are towards their business model. Three of the five would not consider providing a ground mount. In their model, any roof was a good candidate for solar because they used micro-inverters. It didn’t matter that at least 1/8-1/4 of my roof would be under shade at any given time of day…..they would compensate with more panels. Another company only installed string inverters without power optimizers; if there was shade, they wouldn’t do your house.

    They are supposed to be here tomorrow at 0800. The sales rep took a lot of pictures, so they should know what they are getting into. It may be humorous if they show up expecting to trench level and soft ground. I suspect that the job will take three days if they have enough people; day 1: trench and dig/pour footings; day 2: finish trenching, erect racks, and install conduit; day 3: install panels, pull wire, and hook up inverter. We’ll see how it goes, and I’ll post pics along the way if they get it done this week.
    LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]
  • lkstaack
    Solar Fanatic
    • Nov 2014
    • 140

    #2
    Solar Installation Preparation

    Day 1

    My solar contractor started work today but didn't accomplish much. I am dissapointed that they have two weeks blocked off for this install, and I only have a week off of work.

    I knew that the trench would probably have to be dug by hand, but I assumed that they would bring a squad of laborers to do it and knock it out in a day or two. Instead, they brought two electricians to dig it. They started at about 0900 and had completed about 15 feet by 3:30. And that was the easy part on the level lawn. In addition to the two working on the trench, there was the foreman and another man. Those two measured and marked where the footings are to go. At least I got a few of my questions answered:

    • Estimated time for installation: one to two weeks
    • Type of racking: IronRidge standard rails
    • Type of footing: Concrete, 12" wide, 42" deep using sonitubes x 10 footings
    • Orientation and tilt: 215* with only a 20* tilt
    • Panel configuration: 7x3
    • Exact location of panels: 60' down the slope. There are going to be some mean picks
    • Where the inverter will be located: they are planning on running DC up to the panel where my inverter will be
    • Where in my backyard the trench will be run and which part of my sidewalk will be cut: as expected
    • How the trench is going to be dug down my slope: those poor bastards are digging by hand.

    The crew left early before I could talk with them, but I suspect that they will auger the footings tomorrow. That should be interesting. I've attached 3 photos, but they are not very interesting yet. I'm not going to update this thread until there is something interesting to report.

    Day 2-3

    Solar installers continue to focus on moving dirt. Approximately 50 feet has been trenched by hand of the 75 feet required. Six of the ten footing holes have been dug. I expect them to finish trenching and footer holes tomorrow, then pour the footings on Friday. Maybe they'll start racking on Monday. I've included three photos of the trenching and footing holes; not very exciting but its all I got.

    Day 4-5

    Dirt moving is complete. 70 feet of 20" deep trench dug by hand, most of it on a 30* slope. Ten post holes 40" deep dug by hand. The city made their first inspection on day 4 and passed the trenches and holes. Day 6 (tomorrow) should see the posts set in concrete (going to pump about a yard 120 feet from the street to the posts) and the filling of trenches. Racking should begin on day 7 (Tuesday). They apparently feel confident enough about the new plan specifications that they are proceeding without a change approval from city planning (that will follow). I don't know what they submitted, but my site foreman asked me if I was OK with racks 30" of the ground so I can lay weed fabric down when they're done.

    Day 1
    20150330_090305.jpg20150330_155340.jpg20150330_155701.jpg

    Day 3
    20150401_175234.jpg20150401_175321.jpgTrench.jpg

    Day 5
    20150405_174717.jpg20150405_174750.jpg20150405_174807.jpg
    LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]

    Comment

    • lkstaack
      Solar Fanatic
      • Nov 2014
      • 140

      #3
      Solar Component Installation

      Day 6

      Work prevents me from witnessing construction, but I'm able to inspect it when I get home. All ten footings have been poured with support poles leveled and aligned. Conduit was placed in the trench and covered. Access was drilled into the garage with conduit run within the interior from the access point, across the room and then through the wall into the main panel.

      Things should go fast now. I expect the IronRidge racking to be installed tomorrow with conduit run along the exterior of the house.

      Day 7

      Rack is up, inverter is up, and most of the conduit is up. Now all they have to install the panels, pull wire, and hook everything up.

      You'll notice that the rack poles are taller towards the west than they are in the east to keep it level. Its about 64" on the right uphill side and 24" on the left downhill side. Panels seem to be oriented around 200* with a 30* tilt. I haven't been around during the install, so I can't be sure.

      Day 6
      20150406_180835 (1).jpg20150406_180914 (1).jpg20150406_180959 (1).jpg

      Day 7
      20150407_183830.jpg20150407_184135.jpg20150407_184054.jpg20150407_184521.jpg20150407_184634.jpg20150407_184807.jpg
      LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]

      Comment

      • lkstaack
        Solar Fanatic
        • Nov 2014
        • 140

        #4
        My system is almost complete and is scheduled for final city inspection tomorrow.

        Array
        20150408_181935.jpg20150408_182001.jpg20150408_182018.jpg20150408_184128.jpg

        Wire Runs
        20150408_182207.jpg20150408_185406.jpg20150408_185457.jpg20150408_185614.jpg20150408_185622.jpg

        Inverter
        20150408_185752.jpg
        LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]

        Comment

        • gvl
          Solar Fanatic
          • Mar 2015
          • 288

          #5
          If you have anything to add please chime in in this thread I started: http://www.solarpaneltalk.com/showth...unt-vs-rooftop

          Comment

          • lkstaack
            Solar Fanatic
            • Nov 2014
            • 140

            #6
            My ground mount system was completed yesterday, on the ninth day of work. I should also mention that my PV installer also ran a 240v run from my main and across my yard near where I plan on placing a spa.
            -5 days of preparation and digging
            -a day to lay conduit in the trench and pour footings
            -a day to construct the rack, install optimizers, mount the inverter, and run conduit along the exterior of my house into my garage.
            -a day to mount panels, run more conduit, and pull wire
            -a day to connect the wires, receive the final city inspection, fix broken sprinkler line, and clean up

            Although it hasn't produced a watt yet, I know that I have a solid system. Much of it has exceeded my expectations and some have fallen short. It was built on an area of my property that gets the least amount of shade; I only get it in the early morning. It is very solid with excellent orientation and tilt. Power line trenches were dug 20" deep. The inverter was placed inside my garage and the conduit runs are first rate. The biggest gripe I have is that the installer used nylon ties to secure cables to the PV rack. After researching, I still don't know what would be better on the round pipe, but I know that plastic ties are not it. When I complained that I would probably have sagging cables in ten years, the installer advised me to call them and they would repair it.

            I received and completed my SDG&E net metering application yesterday, so now I wait for them to give me the green light to turn it on.

            20150409_181509.jpg20150409_181255.jpg20150409_180945.jpg20150409_180953.jpg20150409_181428.jpg
            20150410_183032.jpg20150410_183121.jpg20150410_183144].jpg
            LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]

            Comment

            • sensij
              Solar Fanatic
              • Sep 2014
              • 5074

              #7
              Just out of curiosity, how did they do the grounding? Sink a rod or two in at the array, and bond it back to the primary?
              CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

              Comment

              • thejq
                Solar Fanatic
                • Jul 2014
                • 599

                #8
                Nice! Looks like they corrected most of the stuff you asked.
                16xLG300N1C+SE6000[url]http://tiny.cc/ojmxyx[/url]

                Comment

                • lkstaack
                  Solar Fanatic
                  • Nov 2014
                  • 140

                  #9
                  Originally posted by sensij
                  Just out of curiosity, how did they do the grounding? Sink a rod or two in at the array, and bond it back to the primary?
                  Yes, they drove two 5' long copper rods into two different 4' deep post holes.

                  You can see one of the rods here:
                  20150408_182148.jpg
                  LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]

                  Comment

                  • lkstaack
                    Solar Fanatic
                    • Nov 2014
                    • 140

                    #10
                    Originally posted by thejq
                    Nice! Looks like they corrected most of the stuff you asked.
                    They did. I would have pressed further on the nylon tie issue, but my research couldn't find the optimal way of securing cables to a round pipe. Nevertheless, I feel they could have used the proper hold-downs on the racks; I'm sure they did for yours. There will be all sorts of critters living under there when the ties ultimately fail.
                    LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]

                    Comment

                    • gregvet
                      Member
                      • Feb 2014
                      • 78

                      #11
                      Originally posted by lkstaack
                      They did. I would have pressed further on the nylon tie issue, but my research couldn't find the optimal way of securing cables to a round pipe. Nevertheless, I feel they could have used the proper hold-downs on the racks; I'm sure they did for yours. There will be all sorts of critters living under there when the ties ultimately fail.
                      One suggestion I would make as I have a ground mount(S:Flex) as well: If your panels are at a sharp angle to the ground (mine is at 35 degrees) and in potential windy environment: Ask your installer for the torque specifications for the attachments of the rails to the concrete vertical posts as well as the attachments of the panels to the rails and check 1 year after installation. My South facing panels have occasional strong winds from the North and West. After 2 years, I just happened to check a nut under the panels and found I could loosen it by hand. I subsequently Googled the torque specs for my system and surprisingly, found many of them were not up to the specified torque but none were over torqued. I called my installer about this and he did not seem surprised given the wind loads and suggested I tightened them and said usually after this first time, they will remain to spec. I'll probably check them yearly...

                      Comment

                      • J.P.M.
                        Solar Fanatic
                        • Aug 2013
                        • 14926

                        #12
                        Originally posted by gregvet
                        One suggestion I would make as I have a ground mount(S:Flex) as well: If your panels are at a sharp angle to the ground (mine is at 35 degrees) and in potential windy environment: Ask your installer for the torque specifications for the attachments of the rails to the concrete vertical posts as well as the attachments of the panels to the rails and check 1 year after installation. My South facing panels have occasional strong winds from the North and West. After 2 years, I just happened to check a nut under the panels and found I could loosen it by hand. I subsequently Googled the torque specs for my system and surprisingly, found many of them were not up to the specified torque but none were over torqued. I called my installer about this and he did not seem surprised given the wind loads and suggested I tightened them and said usually after this first time, they will remain to spec. I'll probably check them yearly...
                        Cyclic or occasional repeated loads such as those caused by wind indicate that occasional or scheduled check of bolting is a good idea, sometimes mandated depending on application. If you can get at them, check a few every now/again and look for loosening , corrosion or other developments, see if you can spot a pattern and respond accordingly.

                        Sometimes lock washers help, but fasteners can always creep from variable external loadings, thermal expansion, corrosion from various sources, etc.

                        Comment

                        • thejq
                          Solar Fanatic
                          • Jul 2014
                          • 599

                          #13
                          Originally posted by lkstaack
                          They did. I would have pressed further on the nylon tie issue, but my research couldn't find the optimal way of securing cables to a round pipe. Nevertheless, I feel they could have used the proper hold-downs on the racks; I'm sure they did for yours. There will be all sorts of critters living under there when the ties ultimately fail.
                          When I did mine, I wasn't as knowledgeable as you're now. So I didn't even notice what type of ties they used. At least being on the ground you can check it once in a few years. Where are many ways to prevent critter living under. As for critters, Fry's sells a solar pest repeller that emits sounds that I heard works well on ridding of rats and gophers.
                          16xLG300N1C+SE6000[url]http://tiny.cc/ojmxyx[/url]

                          Comment

                          • bcroe
                            Solar Fanatic
                            • Jan 2012
                            • 5198

                            #14
                            Originally posted by J.P.M.
                            Cyclic or occasional repeated loads such as those caused by wind indicate that occasional or scheduled check of bolting is a good idea, sometimes mandated depending on application. If you can get at them, check a few every now/again and look for loosening , corrosion or other developments, see if you can spot a pattern and respond accordingly.

                            Sometimes lock washers help, but fasteners can always creep from variable external loadings, thermal expansion, corrosion from various sources, etc.
                            I choose to use Stainless Steel, a bit longer so I can put on 2 nuts. If things are expanding/
                            contacting/straining, a single nut might get worked loose. A lock washer helps, but may
                            not be enough. A pair of nuts locked together will never move, though adjustments might
                            still be necessary. There are also elastic nuts, I am afraid to use them in this environment.

                            Lessor materials than SS may become corroded in place after a while. Bruce Roe

                            Comment

                            • lkstaack
                              Solar Fanatic
                              • Nov 2014
                              • 140

                              #15
                              Originally posted by thejq
                              As for critters, Fry's sells a solar pest repeller that emits sounds that I heard works well on ridding of rats and gophers.
                              I'm more concerned about black widows. I'm a total baby around them.
                              LG280/SE6000/[url]http://tinyurl.com/pav2bn8[/url]

                              Comment

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