3D Motor Maker is correct. The master battery #1 BMS is managing all the other slave BMS’s and as each reaches full charge, the BMS of that battery will stop charging to that battery so current passes to those on a lower charge state. After adding 3 new batteries to our existing 5 battery bank that was 3yrs old, it’s balanced out during running in a couple days.
hi thanks, very useful info thank you. after balancing, do the "RUN' LEDs have to blink together in sequence at the same time, or is that not important?
I always thought that the individual modules have their own BMS, to balance out the cells. Surely if one module is a lower SOC than the others, when the others are fully charged the lower module will catch up it can't be the case that the first battery to reach 100% stops the charging of all the others - that's why they have a coms interface.
Agree with that. If you monitor the comms interface, the 'master' one is controlling the charging of the slave ones, and balancing them. I added a single 1/2 charged one to three others, and they balanced after a few hours.
Thank you for the information I just added another 4 batteries to my previous bank of 4 which is 3 months old... I have the new ones being charged by the old ones at the moment
Which inverter/charger are you using? I have 2 batteries but no charger yet (supply chain issues!). You presumably are charging using solar PV but are you grid tied also?
After 2 months the small variation between my two sets of Pylons (ordered two and then 6 months later another 2) has disappeared. Not say that one shouldn't balance the batteries but it appears they sort themselves out over time.
When voltage is over 49.8 cells are top-ballancing - so it helps to charge the pack to 100% from time to time. Ballancing is very slow (around 20 - 30w so it can take a long time if difference between packs is significant).
@@drsolar I have 4 US2000s fully charged and I added 4 US2000Cs at 50% (You put them first in the loop with one as the master) and after 3 hours they still are far from balanced. I take it if you make them live onto the inverter they will stop balancing? At the moment they are plugged in but the isolator switch on the inverter is switched off.
I don't think this is quite right. When you connect them all in parallel like that, they balance the *voltages*, not the SOC. The light indicate SOC, not the voltage. So even after balancing by doing this parallel connection technique, the SOC values for individual batteries can still be different (even though the voltages are the same). This mis-matched SOC is a big deal because the charger will get an *average* SOC value from the batteries and charge or discharge accordingly. Example, with 3 batteries, if two batteries are at 80% SOC and the third is at 60% (even though the voltages are the same) the charger will see an average SOC of 73.3%. The charger will use this number to charge, for example, meaning that if you set the maximum charge SOC to say 95%, the two (previously 80% SOC) batteries will be being continuously charged with the BMS reading 100% while the third battery is being brought up to 85% SOC whereupon the average SOC will be 95% and the charging will stop. At this point your batteries differ by only 15% (the difference between 100 and 85) , which is better than 20% difference (80% - 60%). To get a better balance between batteries you can charge each battery individually up to 100% SOC and check that the voltages are same on the cells.
Hi, I currently have two us3000c batteries connected to a LuxPower Hybrid inverter. Bought a new battery, same spec and connected it up so that it was the Master. I let the two current batteries charge fully first. I left the data and power caples from the inverter disconnected and then pressed the SW Run switch on the Master. It then started balancing in the same way as your video. Left it overnight and then all the lights were out except the Run led light flashing alternatively on every battery. Does this mean it completely successfuly?
I then switched off the batteries then connected the inverter data cable to the rs485 and the postive power cable to the master and negative to the last battery from the inverter. I then switched on the Isolator switch. But the inverter asks if I want to add a battery. Is it just a question of re-entering the settings? Would pressing the SW run button again with everything now connected to the inverter correct it?
Excellent - I didn't know this - it explains why my top one was often full but the lower was never more than half! Now I know
3D Motor Maker is correct. The master battery #1 BMS is managing all the other slave BMS’s and as each reaches full charge, the BMS of that battery will stop charging to that battery so current passes to those on a lower charge state. After adding 3 new batteries to our existing 5 battery bank that was 3yrs old, it’s balanced out during running in a couple days.
hi thanks, very useful info thank you. after balancing, do the "RUN' LEDs have to blink together in sequence at the same time, or is that not important?
I always thought that the individual modules have their own BMS, to balance out the cells. Surely if one module is a lower SOC than the others, when the others are fully charged the lower module will catch up it can't be the case that the first battery to reach 100% stops the charging of all the others - that's why they have a coms interface.
Agree with that. If you monitor the comms interface, the 'master' one is controlling the charging of the slave ones, and balancing them. I added a single 1/2 charged one to three others, and they balanced after a few hours.
Thank you for the information
I just added another 4 batteries to my previous bank of 4 which is 3 months old... I have the new ones being charged by the old ones at the moment
Did you install the batteries yourself.
@@kevinnadasen3872 I did the entire solar installation myself..
How long did it take for your batteries to ballance?
@@TIMMEH19991 approximately 12hrs..
Which inverter/charger are you using? I have 2 batteries but no charger yet (supply chain issues!). You presumably are charging using solar PV but are you grid tied also?
do thy not all have to be the same voltage if not is there going to be a masive inrush of current to the lower one ?
After 2 months the small variation between my two sets of Pylons (ordered two and then 6 months later another 2) has disappeared. Not say that one shouldn't balance the batteries but it appears they sort themselves out over time.
When voltage is over 49.8 cells are top-ballancing - so it helps to charge the pack to 100% from time to time.
Ballancing is very slow (around 20 - 30w so it can take a long time if difference between packs is significant).
Yes they do balance out over time. It can take up to 3 days to do that from my experience
@@drsolar I have 4 US2000s fully charged and I added 4 US2000Cs at 50% (You put them first in the loop with one as the master) and after 3 hours they still are far from balanced. I take it if you make them live onto the inverter they will stop balancing? At the moment they are plugged in but the isolator switch on the inverter is switched off.
@@TIMMEH19991 they need to charge and discharge to balance.
Hi I'm adding a us5000 to my 3 other us5000. Do I wait for the new battery lights to go off aswell. The other 3 have already gone off
I don't think this is quite right. When you connect them all in parallel like that, they balance the *voltages*, not the SOC. The light indicate SOC, not the voltage. So even after balancing by doing this parallel connection technique, the SOC values for individual batteries can still be different (even though the voltages are the same).
This mis-matched SOC is a big deal because the charger will get an *average* SOC value from the batteries and charge or discharge accordingly. Example, with 3 batteries, if two batteries are at 80% SOC and the third is at 60% (even though the voltages are the same) the charger will see an average SOC of 73.3%. The charger will use this number to charge, for example, meaning that if you set the maximum charge SOC to say 95%, the two (previously 80% SOC) batteries will be being continuously charged with the BMS reading 100% while the third battery is being brought up to 85% SOC whereupon the average SOC will be 95% and the charging will stop. At this point your batteries differ by only 15% (the difference between 100 and 85) , which is better than 20% difference (80% - 60%).
To get a better balance between batteries you can charge each battery individually up to 100% SOC and check that the voltages are same on the cells.
Hi, I currently have two us3000c batteries connected to a LuxPower Hybrid inverter. Bought a new battery, same spec and connected it up so that it was the Master. I let the two current batteries charge fully first.
I left the data and power caples from the inverter disconnected and then pressed the SW Run switch on the Master. It then started balancing in the same way as your video. Left it overnight and then all the lights were out except the Run led light flashing alternatively on every battery. Does this mean it completely successfuly?
I then switched off the batteries then connected the inverter data cable to the rs485 and the postive power cable to the master and negative to the last battery from the inverter.
I then switched on the Isolator switch. But the inverter asks if I want to add a battery. Is it just a question of re-entering the settings? Would pressing the SW run button again with everything now connected to the inverter correct it?