Battery check

[Hutch]

Pottering about in the garage today, and I decided to check the battery voltage on my spare caravan battery.
Using a multi meter. 13.9 volts, strange thought I.checked my motorcycle battery, 13.6 volts. , This is weird.

Back to basics, take the battery out of the multi meter and fit a new battery, measured the old PP3 battery, and it was reading, 5.3 volts, instead of 9 volts ISH.
Rechecked spare caravan battery, 12.6 volts, Motorcycle battery 12.7 volts.
My spare multi meter is in the caravan. If I had it at home I could have cross checked the multi meters.

Just something to think about.

 

[ProfJohnL]

Pottering about in the garage today, and I decided to check the battery voltage on my spare caravan battery.
Using a multi meter. 13.9 volts, strange thought I.checked my motorcycle battery, 13.6 volts. , This is weird.

Back to basics, take the battery out of the multi meter and fit a new battery, measured the old PP3 battery, and it was reading, 5.3 volts, instead of 9 volts ISH.
Rechecked spare caravan battery, 12.6 volts, Motorcycle battery 12.7 volts.
My spare multi meter is in the caravan. If I had it at home I could have cross checked the multi meters.

Just something to think about.

That is a sign of a poorly designed multimeter. I'll bet it wasn't a Fluke , or if it was it was faulty.

 

[Hutch]

It was a Gunsons, pocket meter 2, 4142.
No battery check position, I cannot afford a Fluke meter and unfortunately I didn't condemn one from work before I retired. 🥴but being an retired engineer I should replace the batteries every 6 months , or so.

 

[Buckman]

Throughout my working life I used a Fluke meter for many years and found it to be very accurate. The one time when it did give up the ghost for whatever reason, they replaced the innards FOC although it was probably 3 - 4 years old.

 

[Mel]

Hang on, so a Fluke is a brand of multimeter? Not as in “chance occurrence”?
Mel
Confused and Bewildered

 

[Buckman]

Hang on, so a Fluke is a brand of multimeter? Not as in “chance occurrence”?
Mel
Confused and Bewildered

Of course everyone knows that a Fluke is a brand of multi meter. LOL!

 

[ProfJohnL]

I'm sorry Mel, I never thought about it. To me and most professionals working with electrics/electronics the name Fluke is synonymous with high quality and reliable electrical measurement technology equipment, I could have used Avo, Megger, Gossen, Philips, Agilent/keysight/HP, who's equipment I have and use, but rather like people will often refer to a vacuum cleaner as a Hoover or these days a Dyson, and in caravanning terms, again less so as times go by, a space heater as a "Carver"

 

[LumpyCBR1137XX]

Pottering about in the garage today, and I decided to check the battery voltage on my spare caravan battery.
Using a multi meter. 13.9 volts, strange thought I.checked my motorcycle battery, 13.6 volts. , This is weird.

Back to basics, take the battery out of the multi meter and fit a new battery, measured the old PP3 battery, and it was reading, 5.3 volts, instead of 9 volts ISH.
Rechecked spare caravan battery, 12.6 volts, Motorcycle battery 12.7 volts.
My spare multi meter is in the caravan. If I had it at home I could have cross checked the multi meters.

Just something to think about.

While on charge, bike and car batteries show an accurate 13.6v to 14.1. This will be the same after a run in the car of bike and should only drop a bit if the battery is healthy. This is off load voltage. Check again with the lights on if you can without the engine running, if it drops too much there is a chance the battery is slowly failing. Always worth verifying the measuring instrument first.

 

[Hutch]

While on charge, bike and car batteries show an accurate 13.6v to 14.1. This will be the same after a run in the car of bike and should only drop a bit if the battery is healthy. This is off load voltage. Check again with the lights on if you can without the engine running, if it drops too much there is a chance the battery is slowly failing. Always worth verifying the measuring instrument first.

Thanks, good information, both batteries were checked after a 24 he lapse time. Bike battery is 7 months old, spare caravan battery is about 6 years old.
Both are AGM, bike kept on charge for 48 hrs every 2 weeks over winter.
Caravan spare when I remember.

 

[GrimPol]

In repose a car (leisure) battery will be 12.6V (design). When charging about 14v (You must have a higher voltage to charge). But those figures will show up on a New and Old battery, so actually, it gives you nothing.
A true battery test is when loaded. I ask my wife to drive the 'van by movers whilst I walk and test the voltage. If above 9.6v after 15 secs then all is well.
Or take it around to your local battery retailer and they will test it on load for you. But you have to trust them, eh?

 

[ProfJohnL]

While on charge, bike and car batteries show an accurate 13.6v to 14.1. This will be the same after a run in the car of bike and should only drop a bit if the battery is healthy. This is off load voltage. Check again with the lights on if you can without the engine running, if it drops too much there is a chance the battery is slowly failing. Always worth verifying the measuring instrument first.

And

In repose a car (leisure) battery will be 12.6V (design). When charging about 14v (You must have a higher voltage to charge). But those figures will show up on a New and Old battery, so actually, it gives you nothing.
A true battery test is when loaded. I ask my wife to drive the 'van by movers whilst I walk and test the voltage. If above 9.6v after 15 secs then all is well.
Or take it around to your local battery retailer and they will test it on load for you. But you have to trust them, eh?

Caravan chargers usually produce 13.8V a few do have a higher bulk charge stage at about 14.3V but a holding charge voltage of 13.8.