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  • #16
    Solaredge Reply

    After ruling out shading and water intrusion in the connector, Solaredge suggested:

    > Since this is not environmental we suggest collect ISC data on the modules. (a clamp on meter will be required). Issues of this type come up over time from thermal expansion and contraction. Please verify ISC with values on the back of the modules. This might give us something to go off.<

    So They are suggesting the modules #4, #17 may have a problem.

    Since the modules are land based, I will have to disconnect the connectors, and collect ISC data, and compare the values with the values on the panel .

    It does seem thermal related, as the modules perform sub par until past 12 noon, later they are performing well until sun down.

    I read the testing regimen-

    http://www.solarpaneltalk.com/showth...el-Voc-amp-Isc

    If the data is poor, I will fill out the Solar World form .

    Comment


    • #17
      Originally posted by ecoalex View Post
      After ruling out shading and water intrusion in the connector, Solaredge suggested:

      > Since this is not environmental we suggest collect ISC data on the modules. (a clamp on meter will be required). Issues of this type come up over time from thermal expansion and contraction. Please verify ISC with values on the back of the modules. This might give us something to go off.<

      So They are suggesting the modules #4, #17 may have a problem.

      Since the modules are land based, I will have to disconnect the connectors, and collect ISC data, and compare the values with the values on the panel .

      It does seem thermal related, as the modules perform sub par until past 12 noon, later they are performing well until sun down.

      I read the testing regimen-

      http://www.solarpaneltalk.com/showth...el-Voc-amp-Isc

      If the data is poor, I will fill out the Solar World form .
      Solaredge suggested a clamp on amp meter, why do you have to disconnect anything?

      Comment


      • #18
        Individual Reading

        I don't think you can test individual modules, if they are connected in the string, they have to be tested individually.This will read the ISC value for the module, and compare it with the rating on the module.It should be high noon for a true reading.

        Comment


        • #19
          Originally posted by ecoalex View Post
          I don't think you can test individual modules, if they are connected in the string, they have to be tested individually.This will read the ISC value for the module, and compare it with the rating on the module.It should be high noon for a true reading.
          Correct. Isc is measured by connecting the panel's + lead to its - lead, under the best irradiance conditions available.
          CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

          Comment


          • #20
            Originally posted by sensij View Post
            Correct. Isc is measured by connecting the panel's + lead to its - lead, under the best irradiance conditions available.
            "sc"=Short Circuit. OK

            Comment


            • #21
              You will probably not find a bad panel by disconnecting the leads and doing a
              short circuit current test. That is because the defective part of the panel will
              be bypassed and the remainder will put out the correct current.

              What is needed is to test the panel power under a mppt load. This can be done
              by comparing similar panels, the details will vary depending on the inverter
              setup. In my case of a simple string of 10 panels, the voltage of a weak panel
              was down by 1/3 or 2/3 because those sections were being bypassed.

              Bruce Roe

              Comment


              • #22
                Originally posted by bcroe View Post
                You will probably not find a bad panel by disconnecting the leads and doing a
                short circuit current test. That is because the defective part of the panel will
                be bypassed and the remainder will put out the correct current.

                What is needed is to test the panel power under a mppt load. This can be done
                by comparing similar panels, the details will vary depending on the inverter
                setup. In my case of a simple string of 10 panels, the voltage of a weak panel
                was down by 1/3 or 2/3 because those sections were being bypassed.

                Bruce Roe
                SolarEdge already has access to the voltage and current each panel produces under load, it is reported by the optimizer. If they are asking for Isc, they must be looking for a different failure mode than what you are suggesting.
                CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                Comment


                • #23
                  Originally posted by sensij View Post
                  SolarEdge already has access to the voltage and current each panel produces under load, it is reported by the optimizer. If they are asking for Isc, they must be looking for a different failure mode than what you are suggesting.
                  If every panel is producing proper voltage & current under load, the problem isn't
                  a panel. Optimizer, micros, could be bad, or maybe its the reporting that is bad.
                  Power being lost might be creating a hot spot. I found that weak panels were most
                  likely to show up under strongest sun & load. Bruce Roe

                  Comment


                  • #24
                    Originally posted by bcroe View Post
                    If every panel is producing proper voltage & current under load, the problem isn't
                    a panel. Optimizer, micros, could be bad, or maybe its the reporting that is bad.
                    Power being lost might be creating a hot spot. I found that weak panels were most
                    likely to show up under strongest sun & load. Bruce Roe
                    Perhaps the data showed that some panels were at the right voltage, but the current was low. By checking Isc, they may be able to isolate the problem to the panel or the optimizer.

                    I have been reviewing data of another forum member using SolarEdge, where all the panels have proper voltage, but some have low current. If that is the case here as well, I will be interested in how it is resolved. Bad reporting is definitely a possibility.
                    CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                    Comment


                    • #25
                      Originally posted by sensij View Post
                      Perhaps the data showed that some panels were at the right voltage, but the current was low. By checking Isc, they may be able to isolate the problem to the panel or the optimizer.

                      I have been reviewing data of another forum member using SolarEdge, where all the panels have proper voltage, but some have low current. If that is the case here as well, I will be interested in how it is resolved. Bad reporting is definitely a possibility.
                      Once the panel(s) with low current output under load are found, its just a a matter
                      of swapping the panels or what they connect to, to discover the bad component. If
                      all panels deliver the same V & I, its not the panel. There are 3 72 cell panels here
                      that passed Isc (bypass diodes) but failed under load with max sun. While they may
                      find some app here individually, they won't be allowed to hold back an entire string.
                      Bruce Roe

                      Comment


                      • #26
                        Could anybody cobble together a diagram of what the connections are?
                        • What I gather is there is a Micro Inverter in series with each panel that is reporting voltage current and power.
                        • Each Micro Inverter is strung together (in series or parallel??) with an optimizer at the end of the chain?


                        The symptoms are low power reported at the optimizer for a couple of panels?

                        Solar Edge suggests an Isc test of the bare panel (without micro inverter) to diagnose the low power reported at the optimizer?

                        Comment


                        • #27
                          Originally posted by posplayr View Post
                          Could anybody cobble together a diagram of what the connections are?

                          The symptoms are low power reported at the optimizer for a couple of panels?

                          Solar Edge suggests an Isc test of the bare panel (without micro inverter) to diagnose the low power reported at the optimizer?
                          Here is a link to a white paper that describes the SolarEdge architecture. The OP hasn't given enough information to really troubleshoot, mostly Bruce and I are just guessing at failure modes and how they might exhibit themselves.
                          CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                          Comment


                          • #28
                            Originally posted by sensij View Post
                            Here is a link to a white paper that describes the SolarEdge architecture. The OP hasn't given enough information to really troubleshoot, mostly Bruce and I are just guessing at failure modes and how they might exhibit themselves.
                            Thanks; I think I saw that before just did not commit to memory

                            Comment


                            • #29
                              Confusion

                              There appears to be some confusion.
                              #1 I don't have micro inverters, I have Solaredge optimisers, and a SE6000 inverter on String #2
                              #2, I do achieve full output about 2Pm, up to then the 2 modules under perform.

                              I monitor this using the Solaredge internet monitoring portal.

                              Why would their rep request me to disconnect the trouble modules ?

                              >collect ISC data on the modules. (a clamp on meter will be required). Issues of this type come up over time from thermal expansion and contraction. Please verify ISC with values on the back of the modules.<

                              Comment


                              • #30
                                Originally posted by bcroe View Post
                                If every panel is producing proper voltage & current under load, the problem isn't
                                a panel. Optimizer, micros, could be bad, or maybe its the reporting that is bad.
                                Power being lost might be creating a hot spot. I found that weak panels were most
                                likely to show up under strongest sun & load. Bruce Roe
                                This is exactly what happened with my array. It took my installer 2-3 days to get my SolarEdge monitoring account set up after the install. I noticed right away that one panel was underperforming by a significant amount--each panel did about 2.27-2.42kWh per day, but this one panel did about 0.87kWh. In the morning, the SolarEdge inverter would show 16/16 modules online, but once it got warmer, it would show 15/16 modules online. This went on for 3 days--I noticed this toward the end of a Friday so they weren't able to come out until the following Monday.

                                It turned out to be a faulty SE optimizer. The installer swapped it out. The system has been performing well ever since. The installer weren't sure what to do at first because this was the first time they've had a faulty SE optimizer (of course it would happen to me).

                                We both learned a great deal from this issue. I showed the office folks how to issue site API keys so that folks can do their monitoring on PVOutput. I'll post a thread to describe my install in detail once I get my Rainforest Eagle set up.

                                Comment

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