Slowly getting closer to my desired goal of having a 6000 watt off-grid solar backup system for my house. 5000 watts of panels do a good job of recharging my 16 cell 48V 280AH lifepo4 Daly bms battery build. I'm in the testing phase now and ran into an unexpected hitch that I hope you can explain to me. Every morning I rise and check my battery status with the Smart BMS app and wait for the sun to begin replacing the energy spent on the overnight load, but it never starts automatically. At the "top" of the charge cycle the BMS detects the max charge voltage (3.65V) on any of the 16 cells and immediately sends a 60V spike to the Growatt which triggers the overcharge fault and shuts down the input from the panels. Up to that point everything is doing what it's supposed to. The problem is that once the Growatt shuts down the output to the battery it will continue to recognize (but block) the PV input until dark THEN, sometime during the night, with no PV output, the Growatt quits recognizing the panels altogether (the panel icon disappears). It would seem to me that once the panels started catching some light and producing a few watts, that the Growatt should sense that and restore the PV connection allowing those watts to be utilized. Nope. Nothing "automatic" about it. Every morning I have to switch the Growatt inverter off and put it in the charge only cycle before it recognizes the panels and accepts their current. That seems ridiculously pedestrian for a unit that supposedly has all the bells and whistles attributed to the Growatt low frequency split phase dual MPPT 80A etc... all-in-one solar Swiss Army knife. Would love to hear from other Growatt 6000 users who may, or may not, have a similar situation or anyone who has an idea of why my Growatt won't automatically reconnect the panels when they start producing valuable watts to recharge the battery. Thanks in advance.
Daily reset on Growatt 6000?
- Thread starter gnomie
- Start date
sunshine_eggo
Happy Breffast!
First, the BMS isn't sending a spike. The BMS is cutting off the charger and the charger can't clamp down on the current quickly enough and over-volts. From the charger's perspective, the battery suddenly disappeared.
This isn't a growatt issue. This is a design/build/user issue.
The issues here are:
1) cell imbalance - either you did not top balance the battery before deployment, or you have lost the top balance.
2) incorrectly configured system
The BMS is a safety device. You NEVER rely on it for routine terminations, i.e., you set your equipment to work INSIDE the limits of the BMS, so that the BMS only needs to operate when shit goes sideways.
Confirm BMS balance settings are correct.
Lower your absorption voltage to 55.2V and lower your float voltage to 54V - this should get you to a very high state of charge - 98%+ over a longer absorption time and will allow additional time for the BMS to balance the cells.
If the problem goes away, and you have sufficient battery capacity, you're done.
If you're still getting BMS cut-outs, top balance.
This isn't a growatt issue. This is a design/build/user issue.
The issues here are:
1) cell imbalance - either you did not top balance the battery before deployment, or you have lost the top balance.
2) incorrectly configured system
The BMS is a safety device. You NEVER rely on it for routine terminations, i.e., you set your equipment to work INSIDE the limits of the BMS, so that the BMS only needs to operate when shit goes sideways.
Confirm BMS balance settings are correct.
Lower your absorption voltage to 55.2V and lower your float voltage to 54V - this should get you to a very high state of charge - 98%+ over a longer absorption time and will allow additional time for the BMS to balance the cells.
If the problem goes away, and you have sufficient battery capacity, you're done.
If you're still getting BMS cut-outs, top balance.
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