debron55
New Member
- Joined
- May 4, 2020
- Messages
- 47
Thanks to anyone that can provide some input. I have a Growatt 24v SPF 3000TL LVM in service. I built 2 24 v batteries from CALB 100AH cells and 24v overkillsolar bms. I have a single critical circuit in my home I am wanting to power from this unit. (Computers, WIFI etc.) I also have 4 renogy 320 Watt panels 2p2s. I top balanced the cells and batteries as per will's video. I monitor the BMS' using an apple IPAD. I have the relevant parameters on the Growatt set as follows:
Option: 19 (CV) - 27.3, 20 (Float) - 27.3 21 (Batt Undervoltage) 22.9
here is a video of the BMS on the ipad and the screen of the growatt. There is also a renogy guage on the unit - ignore the AH 100%. I have yet to actually set it up with full and empty settings but the power and volt measurement is accurate. Just the AH guage part is not dialed in
here is the relevent entries from the pvmonitor program from ian.
Here's the issue... early in the morning the the sun comes up and 80% of the time the charger starts creeping up naturally. But twice now I have came out at 9 am ish or so and no solar charging going on... if I reboot the growatt it powers up and will quickly start charging the batteries and powering the load. It continues powering and charging through the day... then about 1 pm generally the unit stops charging the batteries (IE it reaches the CV amount) and the solar charge controller seems to full on stop. The load is transferred to the batteries. Though there is many hours of sunlight left the unit does not use that solar power at all. I can see the line from the panels disappear and the amps and watts go to zero. IF I manually power cycle the unit it will power on and start charging the batteries and carry the load again for a while.
The video shows this happening at 30 second into the short video. You can see from the growatt screen that the battery voltage the unit sees has hit 27.3. at that moment the unit stops using solar power for anything. My understanding is that it should continue to use solar to power the load until solar alone was not sufficient and that it would then augment the solar with battery power... but it appears that the solar just gets completely dropped...
I can provide additional detail if needed... thoughts? ideas? hints or tips?
Option: 19 (CV) - 27.3, 20 (Float) - 27.3 21 (Batt Undervoltage) 22.9
here is a video of the BMS on the ipad and the screen of the growatt. There is also a renogy guage on the unit - ignore the AH 100%. I have yet to actually set it up with full and empty settings but the power and volt measurement is accurate. Just the AH guage part is not dialed in
here is the relevent entries from the pvmonitor program from ian.
Here's the issue... early in the morning the the sun comes up and 80% of the time the charger starts creeping up naturally. But twice now I have came out at 9 am ish or so and no solar charging going on... if I reboot the growatt it powers up and will quickly start charging the batteries and powering the load. It continues powering and charging through the day... then about 1 pm generally the unit stops charging the batteries (IE it reaches the CV amount) and the solar charge controller seems to full on stop. The load is transferred to the batteries. Though there is many hours of sunlight left the unit does not use that solar power at all. I can see the line from the panels disappear and the amps and watts go to zero. IF I manually power cycle the unit it will power on and start charging the batteries and carry the load again for a while.
The video shows this happening at 30 second into the short video. You can see from the growatt screen that the battery voltage the unit sees has hit 27.3. at that moment the unit stops using solar power for anything. My understanding is that it should continue to use solar to power the load until solar alone was not sufficient and that it would then augment the solar with battery power... but it appears that the solar just gets completely dropped...
I can provide additional detail if needed... thoughts? ideas? hints or tips?