Originally Posted by Calson
I have many electronic devices and things like remote controls and remote sensors and the like and when the voltage is too low they will either stop working or work erratically. Stanard testers that check voltage for the batteries is not at all effective as they will only show that a battery is OK or dead and if a battery is at 60% of charge it will still show it as being OK.
I bought a ZTS pulse load battery tester and it applies a load on the battery and provides an exact reading of how much charge a battery is holding and this is for single use as well as rechargeable batteries. It is expensive but it has saved me a lot of grief when trying to diagnose a problem and I can quickly determine if the batteries are the problem and need to be replaced or something else is amiss.
With rechargeable NiMh AA batteries they will recharge faster when they can hold less of a charge. Even my Maha chargers would fail to spot a battery that was supposed to be fully recharged but actually had only 60% of its original charge capacity.
One point not to be missed, before any conclusion on the quality of your battery tester is the fact that most rechargeable AA batteries have a nominal voltage of 1.3 VDC and many electronic devices reacts badly to voltage drop Some devices requires standard non rechargeable AA rated @ 1.5VDC .
For example if you have a device operating with two standard AA serial connected then, your operating nominal is 3 VDC. If you put in two rechargeable instead , then your nominal is 2.6 VDC and this is the equivalent of two almost discharged standard AA. The more sophisticated your device, the more sensitive it is to low voltage.
Just a hint from experience, read carefully the nominal voltage of your rechargeable batteries , you could be surprised
Have a nice day to you