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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

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