Sunnie

Well here we are after just on 3 years of use of Schubart LiFeP 3KWP batteries and the first one that has always shown a different state of charge has failed. The total voltage measured on the battery when disconnected from the circuit is 11.8 V while it is a 48 V battery and gives no lights at all except during the reset process. Have not had much joy with Solarman, who appear to be the sole supplier of the battery, in the past and not much hope by the installer that the warrantee will be honoured. I am an optimist so lets see how they respond.

Hi JanV When you say the system trips, do you mean the battery shuts down or does the inverter shut down? What settings are you using for your system? Check that the battery type is set to "user" and that all the voltages are appropriately set for the charging voltage and float voltage and that the cut off on the inverter is matched to the battery (which on my system is 46.5 V). I do find that the batteries are very sensitive to high current draw and very easily drop below the cut-off voltage of the battery management system despite being almost fully charged. A very brief drop below the cut off voltage switches the battery off and that triggers a shutdown of the inverter. If you don't stand and watch what is happening you don't catch the triggering incident, like something being switched on or using something with a high current draw. I have two 3KW batteries in parallel and can happily run a 2KW kettle for about 6 minutes with my setup during the day when there some sun. The battery voltage will drop very low during that time and would sometimes shut off the battery and that causes the system to die. No auto-recovery. Manual battery reset - after switching the main switch on the battery off, then pressing the reset button on the battery for about 5 sec, waiting till the lights have finished all their Christmas tree show and a few seconds more before switching the battery main switch back on. Sometimes I need to reset all the settings on the inverter if it shuts down that way, with the biggest problem being the return to the default of gel batteries and a very high charging voltage and a higher battery cut-off voltage. Hope this has helped but feel free to drop me more questions if you dont come right.

Hi Kevin I still have the two Schubart batteries in my system. Once you spend the money on the most expensive part of the system it is not worth changing them. They do not communicate with my Charger/inverter though so the settings on the inverter are important. And no. I never did get any information from the supplier on the battery construction and the battery management system shuts the battery off at 46 volts even if its for a second or so making it a frustration. I would not buy these batteries due to lack of support of any kind, but thats what the installer put in with the belief these were better than the socalled Chinese batteries despite these being of Chinese origin. If you want any more info please contact me.

Seems that the drive is nearly full and the swap file size is too large for the available space. Other than the fact that this drops off line from the WatchPower software regularly there does not appear to be any strange behaviour of the inverter. Is there anything that would need to be done to register the control board and would it be possible to update the firmware on the system to one that is more friendly to LiFeP batteries?

Is the new serial number all 5's and 3's, starting with 553555... ? This indicates a "blank" or unprogrammed serial number. That is most unlikely to be caused by firmware corruption; the serial number is stored in an EEPROM chip on the control board. I have an Axpert 5KW/4KW invertor that shows this "blank" serial number and consistently drops out from the WatchPower monitoring software to the extent that the laptop computer with the monitoring software needs to be restarted. Could this blank serial number be the cause? The same computer was used to monitor a similar setup with a Mecer labelled 5KW/4KW Axpert inverter without any problems except taking longer and longer to collect and graph daily data. Sunnie

I recently installed a solar system with 3KW of PV panels and a Axpert SOL-I-AX-5P64 INVERTER and 2 x 3KWP Schubart LiFe batteries. There are very vague specifications available for these batteries and I am wanting to find out the best settings for the charge and float voltages. I have it set up as 30 A max charging current, with 54.8 V CV and float voltage of 53.2 V with a 44.2 V cut-off. The system has now twice shut down completely with a tracked voltage of 47 V when cutting out and loosing communication with the WatchPower software despite the software showing the 44.2 V as the cut off. There are no specs wrt the number of cells and their layout or what BMS system/control is installed. Any information available through this forum?