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  • #16
    Originally posted by jdonalds View Post
    My installer has requested SolarEdge take a look at my system. I believe we lost at least 2KWh just today alone. Cool weather and lots of sun created a bell curve with a three hour long flat top today.
    Would you be able to post pictures or the URL of your public monitoring site (if it has been setup)?
    https://pvoutput.org/list.jsp?userid=59404

    Comment


    • #17
      I'm not sure which model inverter you have, as I don't see the -V5 extension on SolarEdge's website. But the max AC power out is not spec'ed to exceed the nameplate rating on the "HD" series. On the old "A" series (which is what I have) the max AC output may be larger than the nameplate on some models (actually every model except the 6000).

      But note that the Max AC output is different and unrelated to the DC/AC ratio. While it is common to oversubscribe the panel to inverter ration (aka DC kW in > AC kW out) as often PV array output is much less than panel nameplate ratings (aka 365W in your case per panel). Some will argue the PTC or NOCT values are more representative. It does depend entirely on your location, weather, orientation and inclination.

      I assume you have a load side tap? That is to say your inverted is wired in as a breaker in your load center? Do you have a 100amp or 200amp breaker panel? The busbar rating in your breaker panel may be limiting the inverter sizing if you have a load side tap. The other questions is what is your annual electrical consumption? Many power companies limit AC KW sizes based on not exceeding 100% of your historical usage. So this may have also played into the inverter chosen by your installer, OR they just cheaped out.

      HD Series Spec's
      https://www.solaredge.com/sites/defa...tasheet-na.pdf

      A Series Spec's
      https://www.solaredge.com/sites/defa...-datasheet.pdf

      The "good" news is that your panel's output will rapidly decay a few to several percent over the next 6 months or so due to LID and soiling. So the frequency of clipping AS IS will reduce itself over time.

      But by all means press on your installer to at least upgrade to the 6000HD or better yet the 7600HD if it's on their dime. IMHO, Solar Edge's spec's on the HD series is rather misleading. They significantly increased the permissible DC/AC ratio for the HD vs the A series before you void the warranty. But they actually kept the AC's outputs the same -- or lowered them -- versus the A-series. Seems dumb to me. I expect the solid state electronics in the HD models tolerate less over current DC cresting than the old analog inverters.

      The reality is a little clipping is just fine. Sometimes even preferable -- cheaper system cost, better ROI. But as a customer, seeing your potential production fly out the window (even if it is not cost effective to chase those dollars) is admittedly hard to watch.



      Comment


      • #18
        Originally posted by JSchnee21 View Post

        I assume you have a load side tap? That is to say your inverted is wired in as a breaker in your load center? Do you have a 100amp or 200amp breaker panel? The busbar rating in your breaker panel may be limiting the inverter sizing if you have a load side tap. The other questions is what is your annual electrical consumption? Many power companies limit AC KW sizes based on not exceeding 100% of your historical usage. So this may have also played into the inverter chosen by your installer, OR they just cheaped out.


        But by all means press on your installer to at least upgrade to the 6000HD or better yet the 7600HD if it's on their dime. IMHO, Solar Edge's spec's on the HD series is rather misleading. They significantly increased the permissible DC/AC ratio for the HD vs the


        It is unlikely to be any difference in capacity at the MSP as the difference between the SE5000H and SE6000H is very small and often they both use the same breaker size.

        The one thing that would have forced them to use an SE5000H is if the OP has 208V, as the SE5000H supports 208V service bu the SE6000H doesn't
        OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

        Comment


        • #19
          Originally posted by JSchnee21 View Post
          I'm not sure which model inverter you have, as I don't see the -V5 extension on SolarEdge's website. But the max AC power out is not spec'ed to exceed the nameplate rating on the "HD" series. On the old "A" series (which is what I have) the max AC output may be larger than the nameplate on some models (actually every model except the 6000).

          But note that the Max AC output is different and unrelated to the DC/AC ratio. While it is common to oversubscribe the panel to inverter ration (aka DC kW in > AC kW out) as often PV array output is much less than panel nameplate ratings (aka 365W in your case per panel). Some will argue the PTC or NOCT values are more representative. It does depend entirely on your location, weather, orientation and inclination.

          I assume you have a load side tap? That is to say your inverted is wired in as a breaker in your load center? Do you have a 100amp or 200amp breaker panel? The busbar rating in your breaker panel may be limiting the inverter sizing if you have a load side tap. The other questions is what is your annual electrical consumption? Many power companies limit AC KW sizes based on not exceeding 100% of your historical usage. So this may have also played into the inverter chosen by your installer, OR they just cheaped out.

          HD Series Spec's
          https://www.solaredge.com/sites/defa...tasheet-na.pdf

          A Series Spec's
          https://www.solaredge.com/sites/defa...-datasheet.pdf

          The "good" news is that your panel's output will rapidly decay a few to several percent over the next 6 months or so due to LID and soiling. So the frequency of clipping AS IS will reduce itself over time.

          But by all means press on your installer to at least upgrade to the 6000HD or better yet the 7600HD if it's on their dime. IMHO, Solar Edge's spec's on the HD series is rather misleading. They significantly increased the permissible DC/AC ratio for the HD vs the A series before you void the warranty. But they actually kept the AC's outputs the same -- or lowered them -- versus the A-series. Seems dumb to me. I expect the solid state electronics in the HD models tolerate less over current DC cresting than the old analog inverters.

          The reality is a little clipping is just fine. Sometimes even preferable -- cheaper system cost, better ROI. But as a customer, seeing your potential production fly out the window (even if it is not cost effective to chase those dollars) is admittedly hard to watch.


          Thanks for the input. I don't completely understand your question but...

          Our panel is 200A. The SolarEdge Inverter is wired to a circuit breaker. There is also a separate box with a cut off switch.

          We are having some nice weather and daily the graph is clipped at 5,000w when it looks like it could reach to 6,000 if left uninhibited. SolarEdge is hopefully looking at our daily charts and seeing the problem.

          Comment


          • #20
            Originally posted by macaddict View Post

            Would you be able to post pictures or the URL of your public monitoring site (if it has been setup)?
            I'm attaching a couple of snaps from my computer.
            Attached Files

            Comment


            • #21
              Originally posted by jdonalds View Post

              Thanks for the input. I don't completely understand your question but...

              Our panel is 200A. The SolarEdge Inverter is wired to a circuit breaker. There is also a separate box with a cut off switch.

              We are having some nice weather and daily the graph is clipped at 5,000w when it looks like it could reach to 6,000 if left uninhibited. SolarEdge is hopefully looking at our daily charts and seeing the problem.
              SolarEdge will not see a problem other than poor installer. It is within specs just poorly done.
              Most installers wouldn't do this unless the array was on multiple azimuths preventing the clipping.
              Also I doubt it would reach 6kw, more likely 5.5kw, from the graphs.
              OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

              Comment


              • #22
                As Butch said, there is nothing for SolarEdge to do. There's nothing wrong with you 5kW AC inverter. It's performing exactly to spec.

                Since you have a 200 amp load side tap, you could potentially upgrade to a larger inverter -- 6kK or 7.6kW (assuming 240VAC). Either by paying your installer the difference OR arm twisting. BUT, check all of your paperwork: 1) installer contract, 2) township permits, 3) architectural engineering plans, 4) power company interconnect agreement. Your options may be limited:

                1) Did the installer give you what you contracted for? -- if not, hold their feet to the fire. If so, then it's your dime.
                2) If you size up to a larger inverter, you will likely have to redo documents 2, 3, and 4. This may be time consuming an expensive.

                While many here will argue that a little clipping is okay, some even say, good. My concern is that if you are clipping that much now, later in the Spring (before it gets too hot) when the sun is higher in the sky, for more hours, and insolation is brighter, you may have some significantly clipping on your hands.

                If you download SolarEdge Site Designer
                https://www.solaredge.com/us/product.../site-designer

                You can easily model your array based on your panels, optimizers, and different sized inverters taking into account the orientation and pitch of your roof and your approximate location. While there are other more powerful tools. Site designer is easy to use and covers at least 80-90% of what most folks want to know.

                Comment


                • #23
                  At this point I don't think my installer is expecting SolarEdge to find anything wrong with the current unit. They are just asking SolarEdge for advice to see if installing a larger unit is called for given the data. I'm hoping SolarEdge will recommend installing a unit with a higher capacity, the installer will do so, and I will be happy. Of course it could go south but I will insist. All of my dealings with my installer have been very good so far.

                  Comment


                  • #24
                    My installer just called. They had communicated with SolarEdge who agrees my system is way overproducing what they estimated. The panels are generating quite a bit more power than their rated specs. So we are going down the path of installing a replacement SolarEdge inverter that can handle the extra power.

                    When my installer quoted a system back in October 2017 they wanted to use some lower cost lower performing (285w) panels. They wanted 22 panels. I did my own research and selected these rated at 365w which would only require 18 panels. I thought that was smarter because it would mean less chance of shade from trees on some of the outlying panels, and would leave room should I want to install more panels. Also I spent my entire working career in the semiconductor industry and understand quite well the behavior of semiconductors. I knew that if I got better panels they may very well perform quite well. The installer today said the system is producing about 20-25% more than they estimated. This morning it was generating 1.6KW with 100% cloud cover.

                    We haven't yet worked out who is paying for what. They are offering free labor and paperwork. We're working out a cost for the new SolarEdge inverter.

                    It looks like I'll have a SolarEdge inverter to sell. Is there a market for these things?

                    Comment


                    • #25
                      Originally posted by jdonalds View Post
                      It looks like I'll have a SolarEdge inverter to sell. Is there a market for these things?
                      Some.
                      I think you can find them on ebay.

                      If I had more time I'd consider buying it for installation on my church's parsonage

                      Comment


                      • #26
                        Originally posted by foo1bar View Post

                        Some.
                        I think you can find them on ebay.

                        If I had more time I'd consider buying it for installation on my church's parsonage
                        If it was going to a parsonage I'd give you a 10% discount off the going price (whatever that turns out to be!)

                        Comment


                        • #27
                          Hi jdonalds

                          You're the first poster that I have seen on this board with the new LG R-series panels. Are you able to access Solar Edge monitoring? Can you confirm that the panels are actually producing above the STC (365W) at peak sun -- in February???

                          If you don't mind me asking, what was your cost per watt DC installed? Any idea how much the panels themselves were? More than $1/Watt?

                          Your low light performance sounds impressive. My (37) Panasonic panels (330W) do not seem to perform that well without direct sun. Though solar insolation here in NJ is quite a bit less and my tilt is suboptimal. I also have P400 optimizers with a 11.4kW inverter.

                          Be sure to link your system with pvoutput.org to share and track your production.

                          Thanks,
                          Jonathan

                          Comment


                          • #28
                            Originally posted by JSchnee21 View Post
                            Hi jdonalds

                            You're the first poster that I have seen on this board with the new LG R-series panels. Are you able to access Solar Edge monitoring? Can you confirm that the panels are actually producing above the STC (365W) at peak sun -- in February???

                            If you don't mind me asking, what was your cost per watt DC installed? Any idea how much the panels themselves were? More than $1/Watt?

                            Your low light performance sounds impressive. My (37) Panasonic panels (330W) do not seem to perform that well without direct sun. Though solar insolation here in NJ is quite a bit less and my tilt is suboptimal. I also have P400 optimizers with a 11.4kW inverter.

                            Be sure to link your system with pvoutput.org to share and track your production.

                            Thanks,
                            Jonathan
                            Yes we have access to the solar monitoring. That is how I discovered the system was clipping at 5kw. I use the PC application and Android app. I just registered at pvoutput.org with the name "House and Car power". I don't see any uploaded data there yet. I guess it takes some time.

                            Notes on peak output in February. 1) We've had a particularly rainless February. Normal rainfall is 5.1". So far (Feb 22) we have not had any measurable rain. So we've had a lot of sunshine. 2) Our weather has been running in the 40s to 70s F this month; warmer than average. So the panels must be running cool. 3) Redding CA is the 2nd sunniest city in the United States.

                            The LG panels are rated at 365W at NOCT of 44C. So we are likely well below that so I'm not surprised the panels are behaving above "spec". I'm pretty much a novice at this so I may not understand what I'm talking about.

                            Our house/solar panels are very close to due south. Off by just a few degrees.

                            I can't find the original quote with the cost per watt. I now realize I didn't scan it into the computer so it's filed away in the file cabinet. I'll try to dig it up. But the final cost of the entire system was $25,950 for 6.57KW so I guess that works out to about $4/watt. Right? I don't have the breakdown of costs. That figure of course includes all materials and labor.

                            My motivation for installing the system (I doubt if I really have to explain it to this forum) was three fold.

                            1) We have such good sunlight it made a lot of sense. Federal, State, City, and Electric Utility rebates and tax intensives really sweetened the deal.

                            2) We bought a plug-in hybrid vehicle and wanted to charge it with solar. That is working out quite well. The Honda Clarity (fantastic car) never takes more than 2 hours and 5 minutes to charge which is part solar and part grid. Once the car is charged we are feeding power back into the grid. On balance the car is being charged on solar every day. Sweet.

                            3) Rather than focusing on the pay back period I focused on other financial benefits.
                            a. I'm retired and am somewhat dependent on our investments
                            b. Stocks fluctuate and there is risk in a market portfolio
                            c. Gains in the stock market are taxable
                            d. Identity theft could wipe out our portfolio
                            e. Solar systems save money, they don't generate income. They do not generate taxable income
                            f. Solar systems are not subject to Identity theft
                            g. Solar system benefits are likely to improve over time as electric grid rates are bound to rise.

                            So by installing solar we didn't spend money, we simply invested in something other than the stock market. The returns are lower but they are steady. The money invested in solar is much safer and stable than other investments.

                            I'm quite happy with the outcome. I just hope our super hot summers don't result in too much efficiency loss.
                            Last edited by jdonalds; 02-23-2018, 02:03 AM.

                            Comment


                            • #29
                              Jdonalds: Have you run PVWatts to estimate your array's output ? What is your array's azimuth, tilt and zip code "

                              While the inverter may be undersized, and that sounds like it's being addressed, and while the panels over producing, and that will perhaps adjust downward some as the ambient air temps work to increase panels temps., it looks like you're missing quantitative estimates of possible output.

                              PVWatts is one way to get a ballpark # for that output. Read the PVWatts help/info screens a few times, use 10 % system losses and choose the hourly output option. Then, make a few runs. Look for days with daylong high output for, say, Feb., and compare the modeled output for those clear and sunny days with what your array actually produced for clear and sunny days on/around that date. The comparison will not be perfectly accurate, mostly due to the wind and air temp. and - even on clear days - some variation in irradiance. But it it may give you a SWAG of what's going on and also perhaps what to expect in warmer weather. If the model consistently or often predicts an hourly output far in excess of inverter rated max. output, while that is not a smoking gun or a "gotcha" kind of thing, it's probably a good piece of information to have. At the least, if the input is reasonably reflective of actual site conditions with respect to array orientation and equipment, the model's output has shown to be a reasonable reflection of likely long term output.

                              I'll be the first to write that using the hourly output option is a bastardization of the idea behind the model, but if the user is aware of the model's limitations, the model's hourly clear day output on a day can be a reasonable 1st approx. where the actual weather for that day is clear and other conditions are either very similar to what the model is using or those parameters - wind and ambient temp. can be taken into account, provided the limitations of doing so are understood and kept in mind.

                              Also, a respectful suggestion meant in a friendly way: Get ahold of a copy of "Solar Power Your Home for Dummies". 20 bucks at bookstores/Amazon/etc. A good primer that will help you understand what myself and others are writing about.

                              Comment


                              • #30
                                Originally posted by J.P.M. View Post
                                Jdonalds: Have you run PVWatts to estimate your array's output ? What is your array's azimuth, tilt and zip code "

                                While the inverter may be undersized, and that sounds like it's being addressed, and while the panels over producing, and that will perhaps adjust downward some as the ambient air temps work to increase panels temps., it looks like you're missing quantitative estimates of possible output.

                                PVWatts is one way to get a ballpark # for that output. Read the PVWatts help/info screens a few times, use 10 % system losses and choose the hourly output option. Then, make a few runs. Look for days with daylong high output for, say, Feb., and compare the modeled output for those clear and sunny days with what your array actually produced for clear and sunny days on/around that date. The comparison will not be perfectly accurate, mostly due to the wind and air temp. and - even on clear days - some variation in irradiance. But it it may give you a SWAG of what's going on and also perhaps what to expect in warmer weather. If the model consistently or often predicts an hourly output far in excess of inverter rated max. output, while that is not a smoking gun or a "gotcha" kind of thing, it's probably a good piece of information to have. At the least, if the input is reasonably reflective of actual site conditions with respect to array orientation and equipment, the model's output has shown to be a reasonable reflection of likely long term output.

                                I'll be the first to write that using the hourly output option is a bastardization of the idea behind the model, but if the user is aware of the model's limitations, the model's hourly clear day output on a day can be a reasonable 1st approx. where the actual weather for that day is clear and other conditions are either very similar to what the model is using or those parameters - wind and ambient temp. can be taken into account, provided the limitations of doing so are understood and kept in mind.

                                Also, a respectful suggestion meant in a friendly way: Get ahold of a copy of "Solar Power Your Home for Dummies". 20 bucks at bookstores/Amazon/etc. A good primer that will help you understand what myself and others are writing about.
                                Thanks I'll take a look at PVWatts.

                                I do expect to gain information once a proper sized inverter is in place. Without clipping I'll be able to see the top of the bell curve of our daily production. While this February has more sun than most years we do have lots of clear sky days here throughout the year. Temperatures are moderate, seldom very cold mid-day. So my thinking is for 3/4 of the year a new inverter will more than pay for itself in increased production. I expect between 1 and 3 KWH per day increase or about 10% on average. There's nothing I can do about the summer months and it will be interesting to see how much power is lost due to hot panels.

                                I did buy Solar for Dummies. That book is now out of date and needs a rewrite. It is full of duplicate information too. I gained very little from the book. I may be underselling myself calling myself a novice. I do have a 40+ year background in hi tech electronics. It's just that I haven't studied all the in's and out's of solar systems.

                                I still don't see any of my data on PVOutput. isn't it supposed to automatically pull data from my system?

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