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Overkill solar BMS setting to start charging

ohmboy

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Hello again, Now that I have my Overkill Solar BMS app working, which setting do I change for the battery to start charging. I was clicking on something on the app and the Charging arrows flickered for about a second. The Discharge indicator was working when I had something plugged in.
I don't see or at least I don't know which setting to update. My battery is down to 45% and showing 26.29V and 45.1Ah of 100Ah on the app.
Or is this something that I have to update on the solar charge controller? Solar Charge controller is showing 35.46V and 3.2A

Overkill Solar_setting1.jpgOverkill Solar_setting2.jpgvictron100_30_scc.jpg

System:
24V 105Ah LifePO4 battery
Overkill Solar BMS 8s
Victron Smart Solar 100 | 30 solar charge Controller

thanks again, much appreciated.
 
Hello again, Now that I have my Overkill Solar BMS app working, which setting do I change for the battery to start charging. I was clicking on something on the app and the Charging arrows flickered for about a second. The Discharge indicator was working when I had something plugged in.
I don't see or at least I don't know which setting to update. My battery is down to 45% and showing 26.29V and 45.1Ah of 100Ah on the app.
Or is this something that I have to update on the solar charge controller? Solar Charge controller is showing 35.46V and 3.2A

View attachment 214986View attachment 214987View attachment 214988

System:
24V 105Ah LifePO4 battery
Overkill Solar BMS 8s
Victron Smart Solar 100 | 30 solar charge Controller

thanks again, much appreciated.
Turn SW switch setting offIMG_7670.jpeg
 
A few things:

1) Can you please post a screenshot of the main BMS app screen? This thread only has the config screenshots.

2) FYI: You have a lot of good information available in your Victron solar charge controller (SCC) app. It tells you your solar input voltage and current as well as the actual battery voltage and charging current. So I think it already measures what you were attempting to measure when you sparked your meter.

3) Does your system include a shunt-based battery meter? This will accurately track your state of charge and show you net power in/out at any point. Some examples if you don’t have one can be found here.

Out of the box, I’ve found the JBD (Overkill) BMS to be a reasonable approximation, but not as good as a shunt meter.

@Pierre has a lot of experience with this BMS and may have pointers on calibration if you plan on relying on the BMS for state of charge.
 
A few things:

1) Can you please post a screenshot of the main BMS app screen? This thread only has the config screenshots.

2) FYI: You have a lot of good information available in your Victron solar charge controller (SCC) app. It tells you your solar input voltage and current as well as the actual battery voltage and charging current. So I think it already measures what you were attempting to measure when you sparked your meter.

3) Does your system include a shunt-based battery meter? This will accurately track your state of charge and show you net power in/out at any point. Some examples if you don’t have one can be found here.

Out of the box, I’ve found the JBD (Overkill) BMS to be a reasonable approximation, but not as good as a shunt meter.

@Pierre has a lot of experience with this BMS and may have pointers on calibration if you plan on relying on the BMS for state of charge.
OverkillSolar_appHome.jpg
1. Home screen shot shows the discharge earlier today.
3. My system does not have a shunt.
 
Are you running loads now or just charging?

Can you post a picture/refer me to one of the top of your battery bank? I’d like to see how it’s all wired up.
 
Are you running loads now or just charging?

Can you post a picture/refer me to one of the top of your battery bank? I’d like to see how it’s all wired up.
Not using it now. It's currently, supposed to be 'charging'. :)
Here's how I have it wired. Wires from PV out of the solar charge controllers are on the battery posts on top of the battery out cables.

24vSystem.jpg
 
Not using it now. It's currently, supposed to be 'charging'. :)
Here's how I have it wired. Wires from PV out of the solar charge controllers are on the battery posts on top of the battery out cables.

View attachment 215202
Not seeing an obvious reason why your BMS app thinks charging is discharging. I’ve only used iOS version so I don’t know if there are any know issues like this in android.

I don’t see any fusing for the battery. I’d put an MRBF terminal fuse on the battery positive post, or add a class T fuse close to that post.

Also, do you have a fuse/breaker between battery and inverter?

There’s tons of info on the forum for selecting the right sized wires and fuses so you can research it here if you haven’t already.
 
Your system is incorrectly wired. All negative current into and out of the battery must flow through the BMS.
You are seeing charge current on the Victron charger because its connected directly to the battery most negative cell.
Regard the cells and the BMS as the 'battery'.
Remove all cable connections to the most negative cell except the BMS connections.
Connect the Victron negative to the negative buss bar.
 
It also appears you're bypassing your disconnect on the positive.

Hey I started this addiction with that same inverter.

Edit to add, I'd recommend adding a proper fuse to the battery bank.
 
Not seeing an obvious reason why your BMS app thinks charging is discharging. I’ve only used iOS version so I don’t know if there are any know issues like this in android.

I don’t see any fusing for the battery. I’d put an MRBF terminal fuse on the battery positive post, or add a class T fuse close to that post.
Ok, next on the to do list. I just have the battery cutoff switch.

Also, do you have a fuse/breaker between battery and inverter?

There’s tons of info on the forum for selecting the right sized wires and fuses so you can research it here if you haven’t already.
I will add a fuse.

thanks!
 
Your system is incorrectly wired. All negative current into and out of the battery must flow through the BMS.
You are seeing charge current on the Victron charger because its connected directly to the battery most negative cell.
Regard the cells and the BMS as the 'battery'.
Remove all cable connections to the most negative cell except the BMS connections.
Connect the Victron negative to the negative buss bar.
Ok, I will do that now!!!

thank you!!!
 
Hold on. Something is obvious. All your negatives should be coming out of the BMS. Not the post on the battery.
Oh boy. Ok, per @mikefitz ,
"Remove all cable connections to the most negative cell except the BMS connections.
Connect the Victron negative to the negative buss bar.

thanks!!
 
It also appears you're bypassing your disconnect on the positive.
Move the solar charge controller to the bus bar as well?

Hey I started this addiction with that same inverter.

Edit to add, I'd recommend adding a proper fuse to the battery bank.
I will add a fuse, battery to inverter, correct?
 
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