Will plugging solar panels into the B300s side inputs, affect battery calibration?

After adding 2 more batteries, my callibration was way off. (One battery would get stuck in standby at 90% and only after adding Grid Power it would jump to 100%. Another would run down to 1% while the others were at 35%. Things like that.)

It took 12 hours to recharge the whole battery bank using the wall outlet, but now they are all charging and discharging within 1-2 volts of each other.
So i have to wonder if adding extra panel power to some of the B300s will affect calibration.

@St8kout Charging the B300 directly with PV will only fill this directly connected pack.
Due to the difference in platform voltages of the packs, it can’t fully transfer the energy from one cell to the other adjacent pack. For both packs to have the same SOC, you need to connect the solar panel to the AC500.

Have you determined any additional info on this topic?

I have a 460w panel on each of PV1 and PV2. But, I also put a 460w panel on the direct input of the B300.

I have 4 more panels and will eventually have my ground mount with 3x460 on each PC1 and PV2 and will worry about the 7th panel on the direct to battery connection. I just have it that way so I can get more input until I get the ground mounts constructed.

But perhaps I should not do this?

Are you asking if you should use the battery PV inputs while waiting to install your ground mount system? I don’t see why not. About the only downside is running the extra pair of wires for each battery. As brought up before, the APP can’t tell you how much power you’re bringing in for each battery, but with a clamp ammeter and a voltmeter you can determine that yourself. P=IE (watts = amps x voltage. Of course, that will keep changing due to the sun’s position, clouds, shade, etc.
A tip I mentioned elsewhere: On a cloudy/overcast day, I find that my panels can pull in more overall power when facing straight up at the sky instead of trying to aim at the sun, (I can aim my arrays east-west). They take in more overall light this way I guess. But if it’s just partly cloudy then aiming at the sun is better.

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Thanks for taking time to reply.

I just didn’t want to mess up the calibration of the charging from PV1 and PV2. I have only the one battery at this point, so maybe it is that you have the extra batteries that was causing the calibration issues.

Once I get the ground mount constructed (rotating poles), with all 6 panels in use, I won’t mess with the extra panel connected directly to the battery.

Thanks for the tip on positioning. I have been having fun and learning about positioning. On weekend days, I have been “tracking” the sun pretty much all day with ~4 changes. But during the work week, I have been leaving them at ~28* till, due south until I get home, then rotating them to the west to get a good boost for the last 3 hours.

For the load I have on my system, I needed the batteries to reach 100% before it got too late in the afternoon. That’s when I started adding panels directly to the batteries to get them charged in time. As summer is now ending I don’t have to run air conditioning as much, so they get to 100% before noon. I still have to flip the arrays from east to west everyday (then back at night) but it’s not as critical now.

I haven’t tried using an electric heater for winter yet but it might draw as much wattage as my A/Cs. Of course, Vegas doesn’t get freezing cold like everyone else, so I’ll have to see how it works out. I have 3 more 100 watt panels on order, to overpanel one array so I should start seeing 1500 watts on the app display input for pv1. (Currently it’s around 1240 watts.)

It will be interesting to see how the heat works for you…and for me.

I am still building up to run the AC during the day time, which the incoming PV charge will keep the SOC on the batteries. But, the heater I plan to use for the greenhouse will be working against the battery all night. I run the heater for 20 minutes at LOW (1100w?)…so lets say about 300w/h. And depending on when the temp falls below 35, usually around midnight, the heat will come on 6 to 8 times…so, 2400wh used on a cool night.

The challenge is going to be when it is freezing earlier in the evening.