On 8 Nov 2020 14:05:40 GMT, Bob Eager wrote:

On Sun, 08 Nov 2020 13:42:21 +0000, Scott wrote:

My multimeter has a battery test facility that shows the battery as good
or bad (or on the margin). I understand a zinc carbon battery has a
voltage of 1.5 Volts and an alkaline battery has a voltage of 1.2 Volts?
How does it know the difference between a very good alkaline battery
and a very bad zinc carbon battery?.

Alkaline are also 1.5v. You are thinking of rechargeables (e.h. NiMH) for
1.2v.

Thanks. This certainly explains it. I was indeed mistaken.