SRNE SCC charges with too high voltages

[NikR]

In a friends cabin, we replaced a 20 A (Epever) charge controller with a 40 A SRNE SCC (SR-ML2440), and doubling the installed PV to 520 Wp. The batteries are (old) 6 V, 235 Ah FLA in 2S3P configuration. The new SCC is configured for FLA, but the voltages frequently reach and even go beyond 15 V. I changed to manual battery parameters, making sure the voltages are where they should be according to the ML2440 Manual page 18. The voltages remain high.
The batteries off-gas a lot more than before.
Is the SCC broken, or am I missing something?

 

[Tomthumb62]

In a friends cabin, we replaced a 20 A (Epever) charge controller with a 40 A SRNE SCC (SR-ML2440), and doubling the installed PV to 520 Wp. The batteries are (old) 6 V, 235 Ah FLA in 2S3P configuration. The new SCC is configured for FLA, but the voltages frequently reach and even go beyond 15 V. I changed to manual battery parameters, making sure the voltages are where they should be according to the ML2440 Manual page 18. The voltages remain high.
The batteries off-gas a lot more than before.
Is the SCC broken, or am I missing something?

Nope they’re designed this way. You need to change the default settings. You can only do this if you switch to USER mode. Renogy controllers are made by SRNE and have the same issue.

 

[NikR]

Hi Tom, thanks for you answer! I did change to user mode, and the voltages while charging are still way higher than what I set up. I might just get another SCC to see if that solves the problem.

 

[BuffaloTrace]

Lower voltages in the controller settings and use a meter to check output until you get what you need. Write down settings and attach to scc. Its possible the scc just doesn't accurately match up. Always check and don't rely just on the settings menu. I have a couple of renogy rover 60a, and while they work well, the voltage settings never quite match up to the output, and seems to be worse than others. This could be due to different variables in wire size, length of run, etc, but also could very well be the scc isn't calibrated as well as others.

 

[akumd]

Hi Tom, thanks for you answer! I did change to user mode, and the voltages while charging are still way higher than what I set up. I might just get another SCC to see if that solves the problem.

@NikR , what happened with this ? was the issue with SRNE SCC ? how did you resolve it ?

 

[NikR]

@akumd The cabin is not accessible during winter, I'll see what's up when the season starts. There was more than average off-gassing, so I expect to find batteries that lost a lot of liquid. I'll tune down the voltages next time I go.