TLDR: My batteries drain to 50% overnight. When I shut off charging on my MPPT controller, the batteries hold a charge just fine.
I've got a strange issue that I've been chasing down. I still need to do some testing, but any help would be greatly appreciated.
This controller is pulling in power from a solar array to charge a pair of group 24 deep cycle batteries on a small camping trailer. It's been running fine for 4 years.
I noticed on a recent outing that our batteries were oddly low. I took some precautions to finish our trip and brought things back home to test. Here are my findings thus far:
- Batteries have been load tested and are performing fine
- Tested the wiring for excessive draw and found none.
- Went through the logs of the controller and found that a week ago, my batteries would drop 50%.
- Turned off charging function and batteries did not drop at all overnight.
I'm going to see If I can narrow down the issue this evening. I'm curious to know if my controller is not shutting down the charging early enough.
Any thoughts?