Mondo
New Member
- Joined
- Dec 7, 2020
- Messages
- 29
This is my 3rd set of DIY LiFePo4 batteries, and I cannot believe the problem is my cells anymore.
I have a Growatt SPF 3000TL LVM 24V, 8S 280AH Grade A (Eve I believe) cells, and a Daly 8S 100A BMS with bluetooth. I top balanced my cells inside on a bench-top charger, and again after a fews days of settling... so I'm 99% sure it was fully charged when I started the setup. No matter what settings I put in, it goes from 27-27.2V down to 26.3 within an hour or two. If I power cycle the system (kill switch), then it starts charging again, but no more than 8-10A even though I have solar and utility charging on. Within an hour its back to 27V, and either the BMS turns off the Charging MOS (in which case 50% of the time the Growatt Shine app still says its providing charging), or the Growatt stops providing charge and the BMS says Charging MOS is still on (and again 50% the Growatt Shine app might even say its supplying power). At first I could flip the Discharge MOS manually, or worst case the main battery kill switch, and it would start charging again. But now either of those methods or resetting the BMS leads, are kicking it back into charge. I can't figure out what is drawing 2A all the time with everything off... but even with that constant, it should take days to drain as much as it has in hours. Even if I turn everything in my van on, I should only be pulling 10-12A (tested). All switches were off, so the only phantom draw should be the inverter, which is supposed to be 1A or less.
The only other thing I noticed is that the voltage at the battery terminals is 26.6, but at the posts in the Growatt it 27.3, which I imagine means it's reading the PV contribution at the Growatt, but not the BMS... perhaps I need to separate on where it ties in.
Essentially, I'm looking to keep the batteries topped-off, or even better, un-used, while sitting in the driveway on shore power.
When I'm on the road, I'd like the Solar to handle as much as possible, so I know I'd switch Growatt Setting 01 to SOL at that point.
Looking for any advice to get some consistency. This has been over a year of frustration, and way too much wasted money. Let me know what other info might be helpful.
My settings:
I have a Growatt SPF 3000TL LVM 24V, 8S 280AH Grade A (Eve I believe) cells, and a Daly 8S 100A BMS with bluetooth. I top balanced my cells inside on a bench-top charger, and again after a fews days of settling... so I'm 99% sure it was fully charged when I started the setup. No matter what settings I put in, it goes from 27-27.2V down to 26.3 within an hour or two. If I power cycle the system (kill switch), then it starts charging again, but no more than 8-10A even though I have solar and utility charging on. Within an hour its back to 27V, and either the BMS turns off the Charging MOS (in which case 50% of the time the Growatt Shine app still says its providing charging), or the Growatt stops providing charge and the BMS says Charging MOS is still on (and again 50% the Growatt Shine app might even say its supplying power). At first I could flip the Discharge MOS manually, or worst case the main battery kill switch, and it would start charging again. But now either of those methods or resetting the BMS leads, are kicking it back into charge. I can't figure out what is drawing 2A all the time with everything off... but even with that constant, it should take days to drain as much as it has in hours. Even if I turn everything in my van on, I should only be pulling 10-12A (tested). All switches were off, so the only phantom draw should be the inverter, which is supposed to be 1A or less.
The only other thing I noticed is that the voltage at the battery terminals is 26.6, but at the posts in the Growatt it 27.3, which I imagine means it's reading the PV contribution at the Growatt, but not the BMS... perhaps I need to separate on where it ties in.
Essentially, I'm looking to keep the batteries topped-off, or even better, un-used, while sitting in the driveway on shore power.
When I'm on the road, I'd like the Solar to handle as much as possible, so I know I'd switch Growatt Setting 01 to SOL at that point.
Looking for any advice to get some consistency. This has been over a year of frustration, and way too much wasted money. Let me know what other info might be helpful.
My settings:
BMS Setting | BMS Value | Growatt Setting | Growatt Value | |
---|---|---|---|---|
cell volt high protect | 3.4V | 01 | UTL (home) and SOL (Road) | |
cell volt low protect | 3.10V | 02 | 140 | |
sum volt high protect | 27.20V | 03 | UPS | |
sum volt low protect | 25.60V | 04 | SEN | |
diff volt protection | 0.30V | 05 | US2 | |
Chg overcurrent | 160.0A | 06 | LHE | |
dischg overcurrent | 180.0A | 07 | THD | |
type of battery | LFP/liFeP04 | 08 | 120 | |
rated capacity | 280.0AH | 09 | 60 | |
cell reference volt | 3.2V | 10 | 2 | |
sleep waiting time | 3600s | 11 | 30 | |
SOC set | 100% | 12 | 26.8 | |
balanced open start volt | 3.200V | 13 | 27.4 | |
balanced open diff volt | 0.050V | 14 | SNU | |
chg low temp protect | 5°C | 15 | bOF | |
disChg low temp protect | -20°C | 16 | LOF | |
diff Temp protect | 15°C | 17 | AOF | |
18 | BYE | |||
I removed a few which are definitely not related | 19 | 27.2 <-- Won't let me change | ||
20 | 27.2 <-- Won't let me change | |||
21 | 26.6 | |||
22 | SbE |