EG4 18kpv is working on Self-Consumption mode, but the battery does not discharge, and solar only charge the battery.

[JoeX]

I just notice my battery firmware might not be the latest, since I only used RS232 cable (which come with shipping) to update the firmware.
But the RS485-USB cable is also needed to update the BMS.............
Signaturesolar didn't ship that cable with original battery purchase but will ship me one for free after I contact them.
Will update once I receive it.

 

[fnnwizard]

Based on is instruction, it looks like i need separate DC charger in order to calibrate SOC?

@BKY2003 @Quattrohead @wpns run the wall mounts and they prob have the definitive answer to what drives that bms to soc 100% and thus passes the info onto inverter.

There's no way those instructions are valid. You can't drive a cell to 3.700V if pack level is 57.0V unless you intentionally get it out of reasonable balance.

I keep telling @EG4TechSolutionsTeam that pdf is garbage but they keep referencing it. @Zapper77

 

[wpns]

@BKY2003 @Quattrohead @wpns run the wall mounts and they prob have the definitive answer to what drives that bms to soc 100% and thus passes the info onto inverter.

I do closed loop, never hit COVP, get to 100% almost every day. I’ll look up more numbers when I get to a real computer.

There's no way those instructions are valid. You can't drive a cell to 3.700V if pack level is 57.0V unless you intentionally get it out of reasonable balance.

Indeed, crazy numbers. Horse, water…

I keep telling @EG4TechSolutionsTeam that pdf is garbage but they keep referencing it. @Zapper77

When the only tool you have is a hammer, every problem looks like a nail.

 

[wpns]

I do closed loop, never hit COVP, get to 100% almost every day. I’ll look up more numbers when I get to a real computer.

MariaDB [Monitoring]> select max(EG4$Alpha$MaxCellVolt_BMS) from EG4 where EG4$Alpha$MaxCellVolt_BMS >
 0;
+--------------------------------+
| max(EG4$Alpha$MaxCellVolt_BMS) |
+--------------------------------+
|                     3643.00000 |
+--------------------------------+
1 row in set (6.136 sec)

MariaDB [Monitoring]> select min(EG4$Alpha$MinCellVolt_BMS) from EG4 where EG4$Alpha$MinCellVolt_BMS >
 0;
+--------------------------------+
| min(EG4$Alpha$MinCellVolt_BMS) |
+--------------------------------+
|                     2753.00000 |
+--------------------------------+
1 row in set (7.894 sec)

Never hit COVP (or CUVP), and would be astounded if I did in closed loop. I suppose if I locked the CVs on and one of the batteries had charge FETs shorted something could happen, but that's pretty unlikely...

 

[fnnwizard]

MariaDB [Monitoring]> select max(EG4$Alpha$MaxCellVolt_BMS) from EG4 where EG4$Alpha$MaxCellVolt_BMS >
 0;
+--------------------------------+
| max(EG4$Alpha$MaxCellVolt_BMS) |
+--------------------------------+
|                     3643.00000 |
+--------------------------------+
1 row in set (6.136 sec)

MariaDB [Monitoring]> select min(EG4$Alpha$MinCellVolt_BMS) from EG4 where EG4$Alpha$MinCellVolt_BMS >
 0;
+--------------------------------+
| min(EG4$Alpha$MinCellVolt_BMS) |
+--------------------------------+
|                     2753.00000 |
+--------------------------------+
1 row in set (7.894 sec)

Never hit COVP (or CUVP), and would be astounded if I did in closed loop. I suppose if I locked the CVs on and one of the batteries had charge FETs shorted something could happen, but that's pretty unlikely...

That pdf says cell over voltage warning is at 3.700V. So cell over V protection would be higher. But it looks like yours report 100% soc at likely 3.65V?

 

[wpns]

That pdf says cell over voltage warning is at 3.700V. So cell over V protection would be higher. But it looks like yours report 100% soc at likely 3.65V?

I’ll have to see what’s happening inside each battery when it jumps to 100% and see if there’s a common factor.

Of course, EG4 could just tell us.

 

[EG4TechSolutionsTeam]

Based on is instruction, it looks like i need separate DC charger in order to calibrate SOC?

You can also use the inverter on Lead-Acid mode to charge and discharge by voltage.

I just notice my battery firmware might not be the latest, since I only used RS232 cable (which come with shipping) to update the firmware.
But the RS485-USB cable is also needed to update the BMS.............
Signaturesolar didn't ship that cable with original battery purchase but will ship me one for free after I contact them.
Will update once I receive it.

If you need us to send you one (RS485), please let us know.