Epever 5206BP 20 amp controller

[vulcan66]

I'm realatively new to solar and needed some help. I have this EPever 5206BP 20 amp charge controller in a 12v system with a 12v SOK 100AH battery. I set the charge controller charging specs to what I could find online for the SOK 12v 100AH battery. I've hooked up the system today and I see that the charge controller kicks out at 14.1v. I checked my settings and I thought it was suppose to go to 14.6 to be fully charged? Wondering if I'm missing something or if the batteries own BMS charging perimeters are overriding what I set with the charge controller?

I can screen shot my charge controller setting if need be, I just need to hook up the cable to the charge controller to access the settings.

Not sure if I'm missing something here and not sure how important it would be for the voltage to reach 14.6v verses the 14.1v where it kicks out now.

Many thanks!

 

[FilterGuy]

I'm realatively new to solar and needed some help. I have this EPever 5206BP 20 amp charge controller in a 12v system with a 12v SOK 100AH battery. I set the charge controller charging specs to what I could find online for the SOK 12v 100AH battery. I've hooked up the system today and I see that the charge controller kicks out at 14.1v. I checked my settings and I thought it was suppose to go to 14.6 to be fully charged? Wondering if I'm missing something or if the batteries own BMS charging perimeters are overriding what I set with the charge controller?

I can screen shot my charge controller setting if need be, I just need to hook up the cable to the charge controller to access the settings.

Not sure if I'm missing something here and not sure how important it would be for the voltage to reach 14.6v verses the 14.1v where it kicks out now.

Many thanks!

SOKs have a poor balancing algorithm to it is entirely possible it hit a cell over-volt and disabled charging.

 

[sunshine_eggo]

I'm realatively new to solar and needed some help. I have this EPever 5206BP 20 amp charge controller in a 12v system with a 12v SOK 100AH battery. I set the charge controller charging specs to what I could find online for the SOK 12v 100AH battery. I've hooked up the system today and I see that the charge controller kicks out at 14.1v. I checked my settings and I thought it was suppose to go to 14.6 to be fully charged? Wondering if I'm missing something or if the batteries own BMS charging perimeters are overriding what I set with the charge controller?

The BMS is an on/off switch, not a regulator. If something goes out of spec, "NO SOUP FOR YOU!" and it stops whatever is happening. Single cell voltage too high? NO CHARGING FOR YOU! Single cell voltage too low? NO DISCHARGING FOR YOU!

Terminals shorted together? NO NOTHING FOR YOU SHORT CIRCUIT GUY!

I can screen shot my charge controller setting if need be, I just need to hook up the cable to the charge controller to access the settings.

Not sure if I'm missing something here and not sure how important it would be for the voltage to reach 14.6v verses the 14.1v where it kicks out now.

Many thanks!

While 14.6 might be on the label, that requires perfection balance and isn't necessary. 14.2-14.4 can get fully charged quite easily.

Recommend you set:
Boost to 14.4V
Boost duration to 120 minutes
Float to the highest it will tolerate up to 14.2V.

The battery needs to be held at elevated voltage to give the BMS the opportunity to balance the cells. Eventually, you should be able to charge to 14.2-14.4V without any weirdness.

 

[vulcan66]

The BMS is an on/off switch, not a regulator. If something goes out of spec, "NO SOUP FOR YOU!" and it stops whatever is happening. Single cell voltage too high? NO CHARGING FOR YOU! Single cell voltage too low? NO DISCHARGING FOR YOU!

Terminals shorted together? NO NOTHING FOR YOU SHORT CIRCUIT GUY!



While 14.6 might be on the label, that requires perfection balance and isn't necessary. 14.2-14.4 can get fully charged quite easily.

Recommend you set:
Boost to 14.4V
Boost duration to 120 minutes
Float to the highest it will tolerate up to 14.2V.

The battery needs to be held at elevated voltage to give the BMS the opportunity to balance the cells. Eventually, you should be able to charge to 14.2-14.4V without any weirdness.

I really appreciate this reply. I have taken your advice and revised my SCC settings. One question I have as a novice is how to I verify balancing is taking place? The SOK I have is not bluetooth so I have limited visual info. Without accessing the individual battery cells to check the voltage of each cell, how do I know they are being balanced? Maybe this is a dumb question, I don't know. I know the importance of cell balancing with lithium polymer batteries in my rc airplance/drone applications and we have a little device we use on the plug to check the voltage of the individual cells. How do I verify this on these lithium phosphate/BMS batteries for solar applications?

 

[sunshine_eggo]

I really appreciate this reply. I have taken your advice and revised my SCC settings. One question I have as a novice is how to I verify balancing is taking place? The SOK I have is not bluetooth so I have limited visual info. Without accessing the individual battery cells to check the voltage of each cell, how do I know they are being balanced? Maybe this is a dumb question, I don't know. I know the importance of cell balancing with lithium polymer batteries in my rc airplance/drone applications and we have a little device we use on the plug to check the voltage of the individual cells. How do I verify this on these lithium phosphate/BMS batteries for solar applications?

You can't. The 120 minute boost time should ensure it is held at elevated voltage long enough for some balance to occur.

 

[vulcan66]

You can't. The 120 minute boost time should ensure it is held at elevated voltage long enough for some balance to occur.

I see. I did observe some behavior on the battery monitor when the voltage was approaching it's peak that appeared to possibly be the balancing of each cell as the display cycled through different readings for a period before stabilizing. Of course it's something you have to catch at the right moment otherwise might never be observed. Thanks for the help.