Starter battery voltage checking

[camel]

Hi
What/when is the best way to check the starter battery. Battery is original, 10yr old, 30000miles. Motorhome is on EHU at home keeping batteries charged, so realise a constantly topped up battery will always start the vehicle.
I've bought a multimeter, Thursday was 13.5v whilst on hook up, switched charger off and 12.67v. Left charger switched off and today, Saturday, 12.19V.
Do I just keep checking until there is a settled figure or will it continue to drop? What is the 'battery extinct' figure lol.
Thanks
Paul

 

[Eggs]

Hi
What/when is the best way to check the starter battery. Battery is original, 10yr old, 30000miles. Motorhome is on EHU at home keeping batteries charged, so realise a constantly topped up battery will always start the vehicle.
I've bought a multimeter, Thursday was 13.5v whilst on hook up, switched charger off and 12.67v. Left charger switched off and today, Saturday, 12.19V.
Do I just keep checking until there is a settled figure or will it continue to drop? What is the 'battery extinct' figure lol.
Thanks
Paul

It will always have a small drain due to alarm, immobiliser etc.

 

[pappajohn]

Should be 12.6v but as said, some things still use power even after switching off.
12.19v does sound a tad low after a couple of days.
Just had to change my car battery, showing 13 to 14v when running and just after switch off but just over 10v overnight. Still started but only just.

 

[Clivefog]

I work to 12.4 as the cut off, as said there may be things running. If it continues to drop I'd check for a battery drain and consider a new battery.

 

[Podney]

At 10 years old it’s on borrowed time. Treat yourself to a new one and have one less thing to worry about.

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