I wasn’t aware I needed charge more. Good to know. So if I’m pushing 30amps into the battery it will automatically limit it lower when fully charged?Looks OK but you need to charge to at least 14V max volts and hold there until current falls to 0.05C or 15A. Your battery is not fully charged.
Yes, its called tail current. When the cells reach full charge at 3.5V per cell (14.0V) The potential of the cell itself resists the flow of current and amperage drops off rather sharply. This how charge controllers know when to switch over from Absorption mode (constant voltage charging) to No Charge or Float depending on the selection of 2 or 3 stage charging.So if I’m pushing 30amps into the battery it will automatically limit it lower when fully charged?
Choose? Those are the values that the battery’s displaying while charging. I didn’t choose them they are a byproduct.Thinking we need more information.
Some people here have no problem with your charge settings. How did you come about choosing those values?
Yea I definitely know not to blindly trust the bms soc anymore, Can you recommend any shunts? A wireless connection is preferred.Don’t rely on the bms state of charge displayed it is about as accurate as the weather forecast to truly know what the charge level is you need to install a shunt
Victron smart shunt about $130 Bluetooth and ve direct ready I have 3 personally and love themYea I definitely know not to blindly trust the bms soc anymore, Can you recommend any shunts? A wireless connection is preferred.
I assume I’d attached the shunt between the battery positive and positive bus bar?
What was the state of charge displayed and cell voltages just before cut off? Heavy load?Yea I definitely know not to blindly trust the bms soc anymore,
Happened over night, so can’t be certain. Everything looked normal at 8/9pm with over 100amps left on the battery but at 6 am the battery was dead. I know from 12am-6 the only draw on the battery would have been a heater pulling at max 4-5amps.What was the state of charge displayed and cell voltages just before cut off? Heavy load?
What kind of heater only takes 4-5 amps DC? More likely, it's 4-5 amps @ 120VAC, which is 37.5-47 amps @ 12.8VDC.Happened over night, so can’t be certain. Everything looked normal at 8/9pm with over 100amps left on the battery but at 6 am the battery was dead. I know from 12am-6 the only draw on the battery would have been a heater pulling at max 4-5amps.
My best guess is that the 15-20amps I was using during the day for a long period had yet to be fully reflected on the bms soc
Since recharging to 100% I’ve had no issues.
I wish I could have my overkill solar bms send me a notification when I reach a certain percentage or amp/hrs remaining.
A diesel heater uses that much power and it’s only 4-5 amps with the fan blowing full, most the time it’s 1-2amps.What kind of heater only takes 4-5 amps DC? More likely, it's 4-5 amps @ 120VAC, which is 37.5-47 amps @ 12.8VDC.
This was an only a one time thing I rarely run my battery so close to empty. Was stuck in single digit weather for a couple days.In the end more capacity is needed. Although if the BMS indicated more charge remaining than it had it may have implied skipping the evening recharge was OK. Honestly I would spend the monitor money on a second battery.
Maybe keep closer tabs on voltage etc to verify the charge level as the evening progresses and what is left in the
Here’s an update, I’ve been letting the battery fully charge and one of my cells is off from the others. Should I look into do a top balancing?Yes, its called tail current. When the cells reach full charge at 3.5V per cell (14.0V) The potential of the cell itself resists the flow of current and amperage drops off rather sharply. This how charge controllers know when to switch over from Absorption mode (constant voltage charging) to No Charge or Float depending on the selection of 2 or 3 stage charging.
So I currently don’t have a power supply so would you suggest getting one to top balance or would the active balance be the better route?162mV Delta, yes its time to top balance or add a 2A to 5A active balancer.
Cell #4 is high but the voltage didn't run away and trigger an over voltage alarm which is a more serious situation so I wouldn't recommend getting a separate power supply. A separate active balancer is the way to go because it will keep things in line at every charge cycle.So I currently don’t have a power supply so would you suggest getting one to top balance or would the active balance be the better route?