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  • macaddict
    Solar Fanatic
    • Jun 2017
    • 132

    #16
    Originally posted by jasonvr

    Yeah, that's why many of us just upload to pvoutput which does display it. And yes it is logged at 5 minute intervals

    SolarTemperature.JPG
    Isn't this the air temperature coming from WeatherUnderground? I don't think this is the Temperature from the inverter.
    https://pvoutput.org/list.jsp?userid=59404

    Comment

    • ButchDeal
      Solar Fanatic
      • Apr 2014
      • 3802

      #17
      Originally posted by macaddict

      Isn't this the air temperature coming from WeatherUnderground? I don't think this is the Temperature from the inverter.
      If you donate to pvoutput you can get 5 minute data and pull other data like inverter temperature.
      OutBack FP1 w/ CS6P-250P http://bit.ly/1Sg5VNH

      Comment

      • J.P.M.
        Solar Fanatic
        • Aug 2013
        • 14920

        #18
        Originally posted by macaddict

        Isn't this the air temperature coming from WeatherUnderground? I don't think this is the Temperature from the inverter.
        Whatever temperature it is, the inverter internal temp. without aux. forced circulation will probably be something like 25 or so deg C above the immediately surrounding ambient air.

        Array cell temp. is usually above air temp. primarily as f(P.O.A irradiance, wind vector, a few other things). Under bright cloudless skies and a moderate wind and near normal incidence angles, cell temps will run very approx. 25 to 30 C above the amb. air temp. around the array. A dark colored roof will raise the air temp. a few to maybe 5 deg. C above the ground level amb. air temp.

        Comment

        • sensij
          Solar Fanatic
          • Sep 2014
          • 5074

          #19
          Originally posted by macaddict

          Isn't this the air temperature coming from WeatherUnderground? I don't think this is the Temperature from the inverter.
          If you auto-upload from Wunderground, yes, PVOutput's temperature field shows ambient temperature. If you choose not to link to Wunderground, but instead enable temperature data from the inverter in the SolarEdge auto-uploader, it is a temperature reading from inside the inverter itself. Unfortunately, I don't think temperature from both sources is supported, which is why I create two systems on Pvoutput for the same installation. One of them will display ambient temp (rooftop temp form my Davis weather station, when installed), while the other displays inverter temp.
          CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

          Comment

          • jasonvr
            Solar Fanatic
            • Jun 2017
            • 122

            #20
            Originally posted by sensij

            If you auto-upload from Wunderground, yes, PVOutput's temperature field shows ambient temperature. If you choose not to link to Wunderground, but instead enable temperature data from the inverter in the SolarEdge auto-uploader, it is a temperature reading from inside the inverter itself. Unfortunately, I don't think temperature from both sources is supported, which is why I create two systems on Pvoutput for the same installation. One of them will display ambient temp (rooftop temp form my Davis weather station, when installed), while the other displays inverter temp.
            I have both temperatures enabled. There is an option to push the Wunderground temperature to an extended value instead of the standard location (as well as solar radiation). You can then plot ambient temperature on the extended graph. I also added a formula because it comes in Celsius and I want it in Fahrenheit.

            Comment

            • sensij
              Solar Fanatic
              • Sep 2014
              • 5074

              #21
              Originally posted by jasonvr

              I have both temperatures enabled. There is an option to push the Wunderground temperature to an extended value instead of the standard location (as well as solar radiation). You can then plot ambient temperature on the extended graph. I also added a formula because it comes in Celsius and I want it in Fahrenheit.
              Nice, I didn't know they made that change!
              CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

              Comment

              • Woodworkerii
                Junior Member
                • Jun 2017
                • 7

                #22

                Originally posted by jasonvr

                I have both temperatures enabled. There is an option to push the Wunderground temperature to an extended value instead of the standard location (as well as solar radiation). You can then plot ambient temperature on the extended graph. I also added a formula because it comes in Celsius and I want it in Fahrenheit.
                Our new PV system has been online since mid-May. I'm still learning, but with the help of this forum, I was able to switch the inverter's communication method from cellular to Ethernet. A big improvement, but I found that the SolarEdge web browser & iOS app monitoring solutions (privileges as set by my installer) are quite limited. So after reading through some of the past discussions here, I finally got up and running with PVOutput. Donated, and now get 5-min data resolution. Polling interval is set at 15-min to stay within the SE's limit on queries (not to mention the MANY times I hit them throughout the day with my phone app). Using PVOutput, I now have system output, inverter temperature in degrees Fahrenheit, and voltage on the "main" graph/table. On the "extended" data screen v8 and v9, I have Solar Radiation and outside air temperature (API linked from a local/neighbor's station via WUnderground). I hope I'm correct in assuming that the unit for Solar Radiation is W/m^2.
                Here's the problem: I set the outside air temperature to report in deg-F from WU, but PVOutput still displays it as deg-Celsius. If I send the WU temperature data to the MAIN graph/table, it correctly displays the temperature in deg-F. There doesn't seem to to be an option on PVOutput to send the inverter's temperature data to the extended graph. jasonvr mentioned that he applied a formula (deg-C * 9/5 + 32?) somewhere to get the extended graph to plot in deg-F. Where/how do I inject this formula? Do my settings look OK?
                Attached Files
                Last edited by Woodworkerii; 07-05-2017, 04:16 AM.

                Comment

                • jasonvr
                  Solar Fanatic
                  • Jun 2017
                  • 122

                  #23
                  I get Fahrenheit by adding a rule in the "Extended Data Rule" section:
                  v7 = 1.8 * v7 + 32;

                  It would be v9 instead based on your setup

                  Comment

                  • sensij
                    Solar Fanatic
                    • Sep 2014
                    • 5074

                    #24
                    Another small change to consider in your settings... The "summary" column in the extended data is set to "last". If you set that to "change", when you look at your data in the daily view instead of the intraday view, I think it will display the range for the day instead of just the last value.
                    CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                    Comment

                    • J.P.M.
                      Solar Fanatic
                      • Aug 2013
                      • 14920

                      #25
                      Originally posted by sensij
                      Another small change to consider in your settings... The "summary" column in the extended data is set to "last". If you set that to "change", when you look at your data in the daily view instead of the intraday view, I think it will display the range for the day instead of just the last value.
                      Sensij: This is a bit off topic, but can you provide some info to help offset my ignorance with respect to where/how PVOutput gets its cell temp. and P.O.A. irradiance values ?

                      Thanx.

                      Comment

                      • sensij
                        Solar Fanatic
                        • Sep 2014
                        • 5074

                        #26
                        Originally posted by J.P.M.

                        Sensij: This is a bit off topic, but can you provide some info to help offset my ignorance with respect to where/how PVOutput gets its cell temp. and P.O.A. irradiance values ?

                        Thanx.
                        PVoutput can be linked to a Wunderground site and pull the data available. Usually, that is ambient temperature at that station and irradiance measured by a horizonal sensor, if the station is equipped for that.

                        If cell temperature (or at least the backsheet surface temperature of a PV panel) is measured by a device that has the ability to communicate it at some intraday interval, it can be sent directly to PVoutput. You are aware of the complications involved in getting that measurement accurately and reliably, so I won't go into that here.

                        P.O.A. irradiance is not produced or provided by PVOutput, although they have a rough "insolation" function that attempts to show what clear sky output on that day might look like for the location and array orientation entered by the user. I was never successful in figuring out what particular model they use, but it clearly didn't handle temperature correctly when I last looked into it.

                        PVoutput allows some basic function writing using the uploaded data, as in the C to F conversion described a few posts ago. It doesn't really support the more complicated equations necessary to combine time, location, array orientation, ambient temperature, and wind speed to implement models like those used in PVWatts or SAM, or the extensions to those models like what you have worked on that are even more tuned to your system.

                        When I get my weather station active again, I would like to use the CEC model that I translated in python over the winter to see how it compares to my actual conditions and live output. I would still rely on the NOCT model of cell temperature, at least at first, until I can start experimenting with small footprint sensors that could mount directly to the panels. I would be able to upload the model output to the extended values in PVOutput, along with any intermediate calculations (like P.O.A. irradiance) that are useful to see.

                        Probably not the answer you were looking for, but I hope that providing some extra context for those unfamiliar with the terms you were asking about is ok.
                        CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                        Comment

                        • J.P.M.
                          Solar Fanatic
                          • Aug 2013
                          • 14920

                          #27
                          Originally posted by sensij

                          PVoutput can be linked to a Wunderground site and pull the data available. Usually, that is ambient temperature at that station and irradiance measured by a horizonal sensor, if the station is equipped for that.

                          If cell temperature (or at least the backsheet surface temperature of a PV panel) is measured by a device that has the ability to communicate it at some intraday interval, it can be sent directly to PVoutput. You are aware of the complications involved in getting that measurement accurately and reliably, so I won't go into that here.

                          P.O.A. irradiance is not produced or provided by PVOutput, although they have a rough "insolation" function that attempts to show what clear sky output on that day might look like for the location and array orientation entered by the user. I was never successful in figuring out what particular model they use, but it clearly didn't handle temperature correctly when I last looked into it.

                          PVoutput allows some basic function writing using the uploaded data, as in the C to F conversion described a few posts ago. It doesn't really support the more complicated equations necessary to combine time, location, array orientation, ambient temperature, and wind speed to implement models like those used in PVWatts or SAM, or the extensions to those models like what you have worked on that are even more tuned to your system.

                          When I get my weather station active again, I would like to use the CEC model that I translated in python over the winter to see how it compares to my actual conditions and live output. I would still rely on the NOCT model of cell temperature, at least at first, until I can start experimenting with small footprint sensors that could mount directly to the panels. I would be able to upload the model output to the extended values in PVOutput, along with any intermediate calculations (like P.O.A. irradiance) that are useful to see.

                          Probably not the answer you were looking for, but I hope that providing some extra context for those unfamiliar with the terms you were asking about is ok.
                          Thank you. I got what I asked for and that's to say in a positive way. Maybe more comment later, or maybe a thread discussing what may be some ways to use or some limitations to the PVOutput "output", might be useful.

                          I appreciate the response.

                          Comment

                          • macaddict
                            Solar Fanatic
                            • Jun 2017
                            • 132

                            #28
                            Originally posted by sensij

                            If cell temperature (or at least the backsheet surface temperature of a PV panel) is measured by a device that has the ability to communicate it at some intraday interval, it can be sent directly to PVoutput. You are aware of the complications involved in getting that measurement accurately and reliably, so I won't go into that here.
                            How do you know if your system is able to report panel temperatures? I have Jinko Solar panels with a SolarEdge inverter.
                            https://pvoutput.org/list.jsp?userid=59404

                            Comment

                            • sensij
                              Solar Fanatic
                              • Sep 2014
                              • 5074

                              #29
                              Originally posted by macaddict

                              How do you know if your system is able to report panel temperatures? I have Jinko Solar panels with a SolarEdge inverter.
                              There are no commercial systems I am aware of that attempt to measure or report panel temperature. Only home-brew instrumentation for those with the time and money to burn. Solaredge will tell you inverter temperature.
                              CS6P-260P/SE3000 - http://tiny.cc/ed5ozx

                              Comment

                              • J.P.M.
                                Solar Fanatic
                                • Aug 2013
                                • 14920

                                #30
                                Originally posted by macaddict

                                How do you know if your system is able to report panel temperatures? I have Jinko Solar panels with a SolarEdge inverter.
                                Most do not. Additionally, I'd be skeptical of those that do. Most sensor attachment methods are such that they are usually not a very good indicator of cell temp. Also, I've measured cell /panel temp. variations over my array of about something like 2-5 C. depending on P.O.A. and wind vector, making more than a few sensors necessary. FWIW, I can usually and easily find even adjacent cell temp. variation of a deg. C. or so.

                                Also, keep in mind that panel temps., average or otherwise, are not ambient temps.. and the GHI (Global Horizontal Irradiance (or insolation)), needs to be converted to P.O.A. (Plane of Array) irradiance or insolation if information on efficiencies or efficiency comparisons or other parametric information is sought.
                                Last edited by J.P.M.; 07-05-2017, 03:59 PM.

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