ClMo

Update: Yesterday was white strong light from the sun and the error came back after more than 20 days. This is nuts .

Update: I started replacing all of my current sharing cables and in the process I identified the problem. One cable had a ferrule that wasn't thin enough and had poor contact there. I assume the ferrule was placed there to improve contact, but that ended up being the reason for the error 72. By crimping with a different ferrule the error goes away and hopefully forever. Thanks a lot! @Coulomb Enjoy your coffee!

The name into the file is " INFINI V IV 5.6K 56.14" , so they cloned " InfiniSolar V IV" but in reality only they know .

SV-IV-56.14_last_from_easun_banban.rar

SV-IV-56.13.rar

Update: Observation - When is a load of ~5kw and entire energy is from PV , the Vout AC drops to 220V from 230V , and when PV is not suficient and the battery is discharging rise back to 230V. Is this a firmware bug?

Factory version was 56.13, and production date is 08.2024. I could give a try to flash back to factory version . After I replaced the third inverter , there is only 0.1V difference for battery during this time. I could try also a battery calibration but I am skeptical that will solve the issue. The latest firmware from supplier was 56.14.

Updates: After ~ 45 days Error 72 is back, without any intervention/change/touch on the setup. Now is hard to understand this situation and find a solution. I have checked also the old inverter and works fine on bench. Any ideas?

Update: I changed one inverter , the third one, was the inverter which didn't give error often and the problem is solved. I noticed also that one parallel curent cable wasn't tight enough, so I fixed that also. I remember that I checked it before, twice and was ok. So... , now... a good test should be to change back the old inverter and check, but this will not happen on short future... .Anyhow I will check the inverter on another setup to have a conclusion. Many thanks @kuba.cz and @Coulomb for your answers. 🙏

The strings are connected to own earth into a different point than inverters. Works any combination of 3 inverters without error , if one of them(randomly) is closed from button or has PV string disconnected using DC switch breaker. I will check ,anyhow ,what you suggested, thanks! One remark: I saw there is a difference sometimes of 0.2V max between inverters as they see the battery.

All the inverters have the capacitor installed from factory. I equal all the Vout wires having the same length and size , but the same result , Error 72 after a certain time. Next check , I will replace each inverter, one by one with a new one to see if there is any improvement. Any other ideas before what I said ?

Updates: I checked all cables, replace paralel card from each, one by one with a new card, and tested different setups, all with parallel cables connected and untouched. setup1: inv 1 and inv 2 started from button and inv 3 stopped from button with PV panels on, charging only the battery. Works OK. setup2: inv 1 , inv 2, inv 3 started from button and with PV panels from inv3 off. Works OK. setup3: inv 2 and inv 3 started from button and inv 1 stopped from button with PV panels on, charging only the battery. Works OK. setup4: inv 1 , inv 2, inv 3 started from button and with PV panels from inv1 off. Works OK. setup5: inv 1 and inv 3 started from button and inv 2 stopped from button with PV panels on, charging only the battery. Works OK. setup6: inv 1 , inv 2, inv 3 started from button and with PV panels from inv2 off. Works OK. I have changed battery charging curent to: 10A/10A/10A , 20A 20A 10A , 30A 30A 30A, 10A 20A 30A, no solution, error 72 comes after ~5 min. I have measured the output voltage from inverters on different loads, but the values are near below ones: inv1-Vout AC: 229.8V inv2-Vout AC: 230.2V +1m wire longer than inv1 inv3-Vout AC: 229.4V +1m wire longer than inv1 There is no error when is not a sunny day , all works together fine. Any idea what could be ? what to check further?

Could be the above solution also for EASUN SV4?

Hello, There is the following setup: 3 x EASUN SV4 in parallel same firmware 56.14 and same panels config for all( 7 in series for each). 350V , When panels of the third one are connected using DC breaker and the sun is shining , the charge current increase to 20A limit , after 4 to 10 minutes ,Error 72 appears and output of inverters is disable. If panels of the third inverter are disconnected using the DC beaker, everything works fine, and there is No error. I checked the wiring of parallel cables for communication and current and everything is OK. Each inverter is working fine into SIG mode. Could be an interference issue? Indeed parallel cables are along with DC cables for 2 meters into the same cable bed. There in no shield for the cables. Had anyone this kind of issue? Could be EASUN SV4 such sensible at interference?

Hello, is there any battery voltage calibration procedure for EASUN VX IV, ( maybe SRNE) as it is for EASUN SV II?