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Hi @Glen Mokobe Im sorry not at this time.😅 Best Regards

Hi. Thanks for your answer. Actually, i have placed a Axpert King 5000W for grid input. I have installed a "custom" ATS system for switching to grid or to battery input. The system is composed of 2 relay : one for AC GRID input one for the AC Output of the 2 Axpert 8000W i use for solar and battery mode that works The relays are controlled by each AC input comming to the breakers. When the system is on battery, the output relay is ON, and the Grid Relay is OFF, so the house appliances are feed by the 2 Axpert 8000W (max 16Kw output because they are in parrallel). When the batteries are low, the 2 Axpert 8000W inverters will shut down. The AC ouput of the inverters is shutdown so the Inverter AC output relay in my system gos the the OFF position. The grid output relay is activated and AC output is feed by the grid (the Axpert King 5000W is wired in bypass mode for grid input to direct output, the usage of axpert King 5000W here is just for having the metrics of the grid usage only and since the Axpert King also have solar panels connected to him it reduces my grid usage). I have add a timer for switching from grid to inverter output (3 seconds timer, during this time the house is completely with no AC, for allowing the relay to completely moving without spikes) since i am not very confident in my system and i don't want to risk a reverse current flow from the grid back to the inverters and burn them out. Yes, this is a clumsy system but it is the only solution i have found actually for automating this system. The wiring of my house allow only 20A max for grid and we have to rewire completely the house but the owners don't want to make this at this time 😔

@Tiziano On my pylontech batteries, when one cell is at 3,65V it disable charging (seen on US2000 and US2000C). Maybe your battery has and older firmware or faulty BMS with bad charging MOS that keep ON state (experienced on one of my Pylontech batteries). Of course, it will be more safer to lower this voltage value but it is reserved for exepert and void the pylontech warranty Best Regards

Hi @sethmad i have experienced the same problem. But in user mode, if you have not many batteries and juste 3 or 4 batteries, you will have problems like me when the batteries are low the inverter does'nt cut the batteries and the BMS will cut instead. So when the inverter have no batteries voltage it will not restart (experienced with Axpert King inverters, newer models works without but display "BP" error and does not charge the batteries). In USER mode, the inverters calculate the SoC based on batteri voltages, that doesn't represent correctly the real battery SoC. I recommend you to update to the latest Pylontech firmware (for US2000C, 3000C and newer) that modify the charging and floating voltage to 52,8V instead of 53,2V. Sadly, this update is not available for older US2000 batteries (asked pylontech staff but no answer from them) so you have to use a US2000C as master battery if you have one or keeping the USER mode. Best Regards

@Coulomb It may be the case, but i couldn't validate this theory without checking the 2 axpert max Also, one of my axpert max (always the same) sometimes get in fault 09 in the morning. I had to completely disconnect him from battery, grid and PV and completly restarting him. After restart it works normally. The issue appears 2 - 3 times in a month. Maybe a faulty caps or missing neutral screw inside... I will keep you informed about that. Anyway, i have created a "home made" ATS (based on 2 relays, one for grid input and one for inverters output, with a 3 second timer for avoid grid voltage return to inverters output when switching) with a 5K wired on the grid input for having the telemetry and have the possibility to charge the batteries via the grid if required. If will share the wiring plan of my temporary install here very soon. Best Regards

Hi @Powerforum Store tried the King 5K output to the grid input of the Axpert max and it works only when the king is in battery mode. When the king is in grid mode, the main breaker strike again, including the type B breakers on the way. I will stop my 2 axpert max for maintenance and searching if them have not a grounding fault inside....

@Coulomb Thanks ! I will try this 👍 The error where show early in the morning, when the battery where near empty. When the master battery of my second pylontech rack goes out of energy, it sends a shutdown signal to the inverter that also shutdown, even if the master battery of the first rack is working with a 50% of SoC. A feature to disable this shutdown signal could be useful as my batteries racks have sometimes different SoC. Best Regards

Hi I encounters some problems with my two axpert max wired in parrallel mode (no grid input0 , see my other topic about that). One of the two inverters get in faut mode with error 61 (firmware mismatch). The two inverters have the same display firmware and same MCU firmware (46.82). The axperts are old MCU ones. This is compleltely random (the error could occur at startup or after few days). The firmware in one of them is corrupted ? Should i must downgrade firmware ? Nice to hear from you soon Best Regards

Hi Answer after my test. I have connected a King 5K (found in a local detailer) to my installation and no problems for grid mode to battery mode. I have leaved the grid input of my axpert max disconnected. My King 5K recharge my batteries via grid (a relay connect the grid to the King only when the SOC of the batteries are out of 10%). I will try to set a custom full bypass mode by connecting the output of my King 5K to the grid input of my 2 Axpert max. I will pry that the breakers does no trip and the King does not fry if mistake happen...(Ineed the in-out of each inverter is protected by breakers). Best Regards

I expect this thanks for you advice. The earth is coming from the mains. No other earth points. I am expecting the issue found by @Powerforum Store about the parrallel inverters issue whe' they go to grid : The Axpert Max 8 kW has a higher power rating, larger internal components, and different firmware behaviour. When two units run in parallel, they must synchronise their relays almost perfectly. Even a small mismatch in relay timing a few milliseconds between the master and slave can create a larger neutral-earth current pulse during the changeover. The higher power capability also means any transient imbalance can involve more current, making the leakage spike bigger and more likely to trip sensitive or even 40 A Type B RCDs and upstream breakers. In this case, i will try to use a King 5K or Axpert VM III 5K for grind feeding. If it works, my grid input will be capped to 5000W max that are sufficient for all my load when i am on grid (i have more loads only in summer when my cooling system is working, and of course in summer i will be in battery mode due to good sunlight so it will be not a problem.). Best Regards

@Powerforum Store Hi i will try this. Did an Axpert VM III 5Kw could do the trick ? I didn't have a King 5K in spare actually for the test 😣 The axpert 5K could share the same battery bank of the max inverters or it must have separate battery ? If the 5K could use the same battery bank, it could also be used only for charging the batteries from the grid if required. Enabling the grid input of the 5K could be done by an external relay. Also, the output of 5K could go to the max grid input for a complete "bypass mode" . Could you confirm that ? Best Regards

Hi thanks for your answer. Yes, tripping happen when inverter switch to grid mode, when no load on it. One of the inverters even show a F09 error that could be solved by restarting completely the inverter (disconnect loads, battery and grid). The input grid wire is 2,5mm3. Replacement to 6mm3 is planned next month

Yes, it is possible. The earth is not good on the house, i am in location and the owners don't want to repair the installation so...i am embarrasted like that... That does't explain why a 5Kw is working and a 8Kw not. The length and the size is a criteria for the issue ? Best Regards

Hi I received my 40A Type B residual breakers this week. I have installed them, and tried a bypass mode to grid. The new breakers triped. My 2 axpert max inverters get to much power when going to grid mode ? Little precision : i am in triphased in my grid installation, but i can't use all the phases due to technical issues so the inverters input is only on one phase. Since i have 12Kva in triphased, i could have only 20A max per phase. How much the axpert max handle at startup at grid mode ? My old 5Kva axpert King inverters doesn't have to much issue with grid. There is a way to reinstall a 5Kva with it's output dirrectly connected to the axpert max grid input (and of course it's grid input to the grid breakers) ? I suspect that my grid installation doesn't support the axpert max. Actually, the only way to connect my max to the grid is this way : Completely shutdown inverters Disconnect PV input and grid input Startup the 2 inverters Connect the grid input Wait for the inverters to connect to grid Connect the PV inputs But even with this method, the breakers trip. Any ideas @Youda ? 😕 The new breakers pictures are in attachements

Hi @Coulomb thanks for your reply. Yes, it is like that. I have also a 63A residual breaker for AC outpout, it is placed after the two C32A classic breaker for each inverter outpout ( i get inspired by your setup) Yes, your are right. I am waiting for my 2 RCD Type B 40A residual breaker. Since my inverter never charges the batteries from the mains grid (execpted in emergency case when also my gasoline group is also used for charging) the main grid usage never get more that 20A in classical situations. I have choosen the 40A caliburn just for safety. I will never use 63A breaker for main input because my 6mm2 input cable could'nt handle it. When the inverter where installed, i have reversed the fans and check for the relays and i don't find any issue like that. Also the screws for neutral to earth and they are in place. Each inverter AC output is wired in 6mm2. Maybe a faulty breaker or like you said, a undersized breaker. But that doesn't explain why the grid main AC breaker of the house that are 120A sized is tripping... Thanks for your help Best Regards