The monitor is only accurate with no load. If i am running a lot of stuff it can drop down tto the L (low)light.
I use my monitor and check in the morning when nothing has been running and lights off etc... When mine hits the L light I am at 11.9 volts or so. Then its time to charge..
( I did a test. Spent time in the camper during the weekend in my driveway like I was camping. testing the battery with my multimeter as the battery drained. This way I knew what the lights mean..
All I know from my testing is when the last bottom low light comes on im at 11.9 volts and either charge or dont run anything further to draw the battery down past 40%.
Most say those panals are not accurate. But they are actually. Just need to know what your voltage is..
For the people that need help get a reader like this...plug to cig lighter outlet
