Dual battery set up
Hi just wondering if anyone can help me with my dual bettery set up.
I had just one battery hooked up, it was charged and worked fine. Then I decided to get another battery and make a dual battery set up. One was a bit flat so I started off the second, after running all day with the switch set to BOTH the battery was still dead flat. I charged it up before I went out the next time, left it on both, and it drained completely leaving only battery number 2 charged. The only thing I can think is how I earthed the first battery.
Can anyone shed some light on this?
The Red is the positve + lead, Grey is negative -