12/24v Solar Controller --> 6v Batteries
Background: Purchased a used coach, came with a solar panel/controller setup that's connected to Two 6-volt house batteries. I got no paperwork for any of it but scouring the interwebs I at least fou...
Forum Discussion
RICH807 wrote:
So I got a hold of & used a hydrometer on the batteries last night. 1 battery = almost every cell quite weak; tested out at 5-point-something volts about an hour after sunset. The other battery was in better shape but not by a whole bunch. Will be swapping them both out. Low hydrometer readings can mean the battery is not fully charged or needs to be equalized. ie It does not just mean that the battery has failed.
Have the batteries load tested which will fully charge then first, then you'll know.
ETA: I found out these batteries were put in sometime around the beginning of 2016 (when the previous owner had the solar put in).They should last 3+ years if not abused or were used a lot.
What you've posted MAY point to bad batteries but I'm not sure the batteries were fully charged (ie 14.8V bulk then absorb) let alone equalized.
For your panel: 12V panels are usually a 4x9 array of cells, easy to verify. 36 cells at 0.5V so 18V. Disconnect the controller input wires and measure to confirm. You may also be able to use a mirror to see a label.
