Post by rogerb on Apr 13, 2020 11:21:25 GMT
Following my recent post about battery charging you may question how you know the state of charge of a battery (assuming it is not simply totally flat!). Well you can check the terminal voltage if you have an appropriate meter. I will say I've always had an analogue Multimeter (one with a pointer on a scale) and it has paid for itself many times over. Note: a Multimeter (as opposed to simply a Voltmeter) is a meter that will measure other values such as current and resistance - which can be very useful (photo 1).
However, you can now get a decent digital type (photo 2). There are quite decent ones on the market that are not at all expensive. I have bought one from a popular tools / hardware supplier that you often spot on your local industrial estate. The helpful feature is that they show the voltage more accurately, i.e. part of a volt. So I now see it's "x value & point something", if you know what I mean. Hope this helps and by the way, it is best to leave voltage checking for some hours after full charging as the battery will settle down to its true state.
Typical voltages and state of charge:
12.78V - just been charged
12.60V - full capacity
12.35V - 75%
12.06V - 50%
11.70V - 25%
10.50V - fully discharged
However, you can now get a decent digital type (photo 2). There are quite decent ones on the market that are not at all expensive. I have bought one from a popular tools / hardware supplier that you often spot on your local industrial estate. The helpful feature is that they show the voltage more accurately, i.e. part of a volt. So I now see it's "x value & point something", if you know what I mean. Hope this helps and by the way, it is best to leave voltage checking for some hours after full charging as the battery will settle down to its true state.
Typical voltages and state of charge:
12.78V - just been charged
12.60V - full capacity
12.35V - 75%
12.06V - 50%
11.70V - 25%
10.50V - fully discharged
