Couple of battery voltage & charging question
Have had an AGM battery (one) for a year now, not that being AGM necessarily matters. Never dry camp. Also bought a Progressive Dynamics converter/charger upgrade for it. Recently installed an LED ...
Forum Discussion
myredracer wrote:
Update...
After the battery was discharged somewhat from using the tongue jack and slide, the next day the voltage stabilized at 13.2 volts so all is good there.
I disconnected the battery (after voltage read 13.2) and the next day the resting battery voltage read 12.8 volts so okay there too.
Interestingly, the battery voltage using my HF multi-meter read 13.9 volts, waaay off. Junk!!
I don't know what the battery specs are, but IMO you are not in the clear yet from what you have posted.
12.8 is at the bottom of the range for the resting voltage of this battery when full, where 13v is in the middle. See graph bottom right scroll down.
One day does not tell the tale for resting voltage after a full recharge either. You want to check that over a few days and see that it does not self-discharge much (there is a spec for that too, as you can see here for this particular battery)
You could well be undercharged and a bit sulfated, especially if your battery also specifies 14.8ish for a recharge like this one does.
Yes, a multi-meter will start to read high for voltage when its own battery is getting flat. It happens slowly so you might not notice right away.
http://www.wegosolar.com/products.php?product=SKR%252d125AGM-Stark-AGM-12V-Solar-Battery-Sealed-125A
Note the float voltage for this one is 13.6-13.8 at 25C, nowhere near that 13.2. You must know the actual specs for your actual battery.
