Jump to content


  • Content Count

  • Joined

  • Last visited

  • Days Won


Everything posted by Calvin

  1. From the manual: Working Temperature 0℃~50℃ Charge -10℃~50℃ Discharge Having said that, I think you are right to be worried. High temperature is one of the biggest factors affecting battery life. I am building an actively cooled enclosure for mine - I want them to stay near 25°C.
  2. Bought directly from ICC. Fully up to date. R2500
  3. I have a very similar installation (12x365W on each of my Kings). I ran them in 3S4P initially and subsequently changed them to 2S6P. This made them run very much more reliably - they are VERY fussy about the max voltage, and 3 72-cell panels in series is simply too much. High temperatures and SCC trips no longer happen at all since I changed them. Having said all that, your problem seems to be more than that. My change to 2S had no discernible effect on peak production - I regularly got 4000W from each set of panels in good conditions, and still do. What is your location and the
  4. If I remember correctly he has the SOL-I-AX-5NB (MKS II). Are these not King firmware?
  5. Also the specs for VOC are at 25C, with a temperature coefficient of -0.29%/°C. That works out to about 0.4V/°C. That means that at 20°C you will be at 145V, rising to about 149V at 10°C. As @Coulomb has stated, the 145V is not a guideline - it is an absolute, do not exceed under any circumstances limit.
  6. Below the graph as promised for your 26 degree roof angle. Peak production would be about 0.97W per W installed, or 6.36kW. Note that all these figures are at 25C panel temperature. Actual production would be about 10% lower at 55C and 7% higher at 5C.
  7. You mean like this? Click on drop-down next to your user name at the top of any page. Select "Account Settings" then "Signature".
  8. These panels output approximately 10A at 40V = 400W. You have 3S2P so you should be getting about 120V/20A. It seems that they are performing as expected. To get more current, put them in 2S3P - that will give 80V/30A. Same power, but good for other reasons. Or, buy more panels....
  9. Voltronics sell a lot of inverters, and operate at the "value" end of the market. Your SCC happened to pop - sometimes "stuff" happens. (Had your panels been 3S, they would probably have refused the repair based on the Voltage being out of spec - at least then they may have had a point.) The fact that the suppliers/manufacturers are now inventing new rules to dodge their warranty obligations in no way means that there is anything wrong with the way your system is configured. It is just a bunch of sleazy crooks doing their thing. (I have 4 of these installed - what was I thinking
  10. Technically you probably can insist on a repair under the Consumer Protection Act (any lawyers out there?) Nowhere in there brochures or installation manuals do they mention these restrictions. Even now they say "we suggest" rather than "your warranty will be void if ...". In practice name and shame may be an easier option. Start by telling us who the supplier is, so that we can avoid them. Or say to them "OOPS - did I say 2S6P? I meant 3S4P!"
  11. WOW. Even by their incredibly low standards, both in customer service and technical competence, this is surely a new low. As @Coulomb and others have documented endlessly, and I have personally experienced, these inverters do not work properly in 3S configuration with 72 cell panels. So now we can't use 2S and we can't use 3S. I guess the only valid answer is to stop using Voltronic's products completely. Darwin will surely smile when they go into well-deserved bankruptcy...
  12. These panels have a maximum open circuit of around 47.6V at 25C which will go up to about 50.5V at 5C. 8 Panels in series will hence have a maximum of 404V, well under the inverter's maximum MPPT voltage of 425V. 16 panels @410W would be just over the maximum of 6500W allowed, but as you correctly say with the panels at different orientations you will never get there. (If you let me know the inclination of the panels I can generate a graph of your potential solar production for you) Assuming that I looked at the correct data sheets, you system would be nicely optimised.
  13. I think it is probably only due to voltage - your temperatures are going down due to the SCC tripping because of the over-voltage. My inverters (Kings, but similar SCCs) would throttle on SCC temperature once the SCC PWM got to 87C, but that was a gentle reduction to keep the temperature at 86-87. It did not trip the SCC (A key difference is that you have only about 2kW of panels on the inverter - I have 4.3kW - so I don't think that there is enough power to get the SCC up to 87C). On the other hand, if the PV voltage got too high the SCC tripped, which is what yours appears to be doing.
  14. I think that is the MKS, which is good news for you - @Coulomb and friends have developed pathed firmware for those that eliminates some of the worst bugs, and adds some nice features. Might well assist in stopping the drop out you saw. Something does not add up - you have voltages that are consistent with 3-in-series (3S) 72 cell panels, but you have only 8 panels, (perhaps even 60 cell ones) which means 4S2P or 2S4P. Will be interesting to see.
  15. Sadly I am not aware of any way of getting this data from the inverter. I was also interested in getting this, and ended up making a pyranometer (using a small panel, a load resistor and a microcontroller with an analogue input) to measure it directly. It worked surprisingly well, as long as you size the load resistor so that the panel operates in the linear part of it's curve. The main problem is that it responds almost instantly to eg. clouds moving in front of the sun, whilst the Axpert's SCC reacts several seconds later.
  16. I have a program that can calculate it for you. What is the panel setup: I need location (GPS) panel orientation and tilt.
  17. @vwykj, if you want to ensure that a member gets a notification that you asked for their help, use @Coulomb instead of Coulomb. This particular question does not need his specialised expertise. Setting 2 on paralleled Axperts is independent and cumulative: 3 US3000s have recommended total charge current of 37x3 = 111A. You can set one inverter at 60A and the other at 50A to get 110A.
  18. The real Voltronic inverters are sold as Axpert, Mecer, RCT, Kodak and many more. Apparently anybody who buys a container full can have their own logo put on it by Voltronic. There are of course no rules in the world of illegally copying other companies' designs, but as far as I know all the inverters sold as "Axpert type" are clones. Generally the clones are to be avoided.
  19. The real Axperts (also sold as Mecer, RCT, Kodak and many other names) are manufactured by Voltronics, and do not cost much more than the clones. The clones are often called "Axpert type" inverters and are not good - avoid them. BTW, there is now a 24V Pylontech - the UP2500. The main problem with using your existing trolley and this battery (apart from the fact that the voltages may not be right) is that it locks you into 24V. Most future upgrade paths would probably be better with 48V, although the option you mentioned (Axpert 3kW) is a 24V inverter, and incompatible with the battery
  20. I ended up using the "cheap-and-nasty" Axperts. My thinking was essentially the same as in RAID disk arrays - I did not want to be dependent on a single 15 or 20kW inverter. I bought three 5kW Axperts and have a fourth as spare - still much cheaper then the blue option. BUT - the Axperts are very problematic. OK but not first-class hardware, poor firmware and unbelievably poor support. Generally you need external software to manage them effectively - If you want a hands-off solution, I would not recommend them.
  21. This may not be quite right - my understanding is that most (all?) big inverters (> 8kW) are 3 phase. Certainly all the ones I could find with a quick Google.... Most smaller inverters can also be paralleled in 3-phase configurations.
  22. Hi Richard - thanks for that. I do in fact already use a PID controller algorithm in my software.
  23. The 80A is essentially the maximum recommended value. If your batteries will charge fully at a lower setting, by all means use it. Generally, lower current is better as the power wasted (because of the internal resistance of the battery) goes up with the square of the current. This wasted power also heats the batteries, which is not a good thing.
  24. I have done this, and it is indeed not trivial if you want to do it well. The biggest challenge turned out to be finding how much excess PV is in fact available. When the battery is charging at the maximum allowed current (or is full) the SCC will clip it's output to what the system can use. First I tried looking at the MPPT voltages - the logic being that if they are higher than the maximum power point, the SCC has pushed them up to reduce power, so there must be spare PV out there. This worked OK but not fantastically - perhaps complicated by the fact that I have 3 inverters in p
  • Create New...