I have 2 MPPT Controllers that are about 7 years old. I received this error message 4 days ago. System seems to be operating properly. I would like to know what error code #66 is and what are the potential effects to the system. Thanks!
Same here after the MPPTs firmware update
Have you updated the rest of the system?
Did you check the settings compared to the rest of the components?
If it is programmed correctly then theoretically nothing they should be able to sort themselves out.
What batteries do you have?