diy solar

diy solar

Growatt SPH4000 and Seplos not stop the charging of battery

jsolar

New Member
Joined
Oct 15, 2021
Messages
43
Hi,
I have Growatt SPH4000 inverter and LiFePo4 battery 200Ah with Seplos BMS. I have one big issue with BMS or with the inverter. My battery is fully charged but the inverter does not stop charging. The inverter is set at the end of charging (example 90%) but the inverter continues to charge until BMS does not activate warning. Inverters have info from BMS and stop to charge the battery but also and not use energy from the battery. Every day I must change the total capacity or the remaining capacity on the battery. Then the inverter starts to use energy from the battery.I had contact with Seplos and Growatt support but did not get any usable response.

From growatt i get responses similar like: Growatt not support issues with battery which is not from Growatt. The inverter is set to SOC to which the battery can be charged (90%). On the Web application from Growatt SOC of battery is presented.

From Seplos I get instructions on how I must set the Growatt inverter. This instruction I got with the inverter and this response is not helping me.

I do not know what I did wrong. Can someone help me?

On BMS:
1653507651739.png


Settings on inverter:
1653507929794.png
 
Hi jsolar,

we have exactly similar problems with
Growatt SPH 10000TL3 BH and Enershare battery system.

Immedeatly when the communication via CANBUS starts
Growatt starts to charge batteries from GRID.

This will happen in all priority modes
Load First
Bat First
Grid First.

And AC CHG is OFF.

Cloud server is reporting the increasing value of SOC.
Growatt will charge upto 100% even the upper limit has been defined.
The charging is finally stopped by battery BMS control.

We have never succeeded to discharge the batteries under Growatt's control!

So, please did you find any solutions in your problems.
 
Hi jsolar,

we have exactly similar problems with
Growatt SPH 10000TL3 BH and Enershare battery system.

Immedeatly when the communication via CANBUS starts
Growatt starts to charge batteries from GRID.

This will happen in all priority modes
Load First
Bat First
Grid First.

And AC CHG is OFF.

Cloud server is reporting the increasing value of SOC.
Growatt will charge upto 100% even the upper limit has been defined.
The charging is finally stopped by battery BMS control.

We have never succeeded to discharge the batteries under Growatt's control!

So, please did you find any solutions in your problems.

Hi jsolar,

we have exactly similar problems with
Growatt SPH 10000TL3 BH and Enershare battery system.

Immedeatly when the communication via CANBUS starts
Growatt starts to charge batteries from GRID.

This will happen in all priority modes
Load First
Bat First
Grid First.

And AC CHG is OFF.

Cloud server is reporting the increasing value of SOC.
Growatt will charge upto 100% even the upper limit has been defined.
The charging is finally stopped by battery BMS control.

We have never succeeded to discharge the batteries under Growatt's control!

So, please did you find any solutions in your problems.
You must check tri think:

- In option 'Load first' you must have a setting for the lover limit for discharge. When BMS reported to SOC below 10% then the inverter immediately started to charge from the grid until 15%. Inverter will stop to discharge when SOC is 15%.

- If the battery is constantly charging to 100% check time slots in 'Battery first'. Maybe you have some of 6 option settings to 'On'. If you do not need charging from the grid all options must be 'Off'.

- Growatt inverter will charge the battery until BMS does not change status to 'Warning'. After that the inverter does not use energy from the battery. Using energy from the battery will be started when SIC is less than 96%. That is a big issue. You can do one 'Work around'. On the BMS disable 'Intermittent charging function' to Off. After that the inverter will stop charging when the voltage of the battery is 'Total_voltage overvoltage protection'.
1654543477777.png
 
Last edited:
Hi jsolar,

thank you for your fast respond.
Did you solved your original problem ..."My battery is fully charged but the inverter does not stop charging"...
with these parameters settings?

cheers r
 
Hi jsolar,

thank you for your fast respond.
Did you solved your original problem ..."My battery is fully charged but the inverter does not stop charging"...
with these parameters settings?

cheers r
Yes, I solved my problem with this parameter.
 
Lifepo4 chemistry using absorption could bring battery to over 100+% SOC at only 3.444 V. Threshold is dependent on cells manufacturers. Relaying on SOC is not possible with this chemistry. Shunt is never 100% accurate. So only way to get it right is to go after battery total voltage and using one of the cells for benchtop observation to figure absorption and low current cut out times. Once you master this process it will be easy to figure out everything else. This is how professional battery builders do things. You need to learn cell chemistry inside out to figure work around where cells chemistry is working best.
 
You must check tri think:

- In option 'Load first' you must have a setting for the lover limit for discharge. When BMS reported to SOC below 10% then the inverter immediately started to charge from the grid until 15%. Inverter will stop to discharge when SOC is 15%.

- If the battery is constantly charging to 100% check time slots in 'Battery first'. Maybe you have some of 6 option settings to 'On'. If you do not need charging from the grid all options must be 'Off'.

- Growatt inverter will charge the battery until BMS does not change status to 'Warning'. After that the inverter does not use energy from the battery. Using energy from the battery will be started when SIC is less than 96%. That is a big issue. You can do one 'Work around'. On the BMS disable 'Intermittent charging function' to Off. After that the inverter will stop charging when the voltage of the battery is 'Total_voltage overvoltage protection'.
View attachment 97527
surely the over voltage protection is a safety feature only. Are you saying is an alarm is triggered on the bms then the inverter will stop charging? im having the same issue and cant stop the inverter from charging to 100%. really frustrating
 
Back
Top