Good/bad batteries or parasitic drain?

[PelicanHead]

I've asked my nephew to drop his off.
I could have tried mine on my car battery but that's been taken for repair.
I have tried a 1.5v AA battery and it reads 1.72, which brand new and under no load seems correct.

I have a LAP multi meter that is now showing the battery sign, meaning new battery required.
Batteries batteries everywhere, what would we do without them!

[E-bmw]

Well if it reads the same the only other possibility I can think of is high internal resistance (on their way out) can artificially raise the voltage, but then we already knew they were pretty much goosed anyway.

[littleredrooster]

PelicanHead said:

I have tried a 1.5v AA battery and it reads 1.72, which brand new and under no load seems correct...

Errrm...no, I don't think so...once again it sounds like at least +10%/15% over actual value. I'm still suspicious.

[Griffith4ever]

littleredrooster said:

PelicanHead said:

I have tried a 1.5v AA battery and it reads 1.72, which brand new and under no load seems correct...

Errrm...no, I don't think so...once again it sounds like at least +10%/15% over actual value. I'm still suspicious.

hehe - no, it should read 1.5v. Your meter battery is dying. Absolutely no way a 1.5v AA would ever read 1.72v. It woudl read 1.499 / 1.5v. (I test them often).

Spend £8.47 and tomorrow, you'#ll have correct readings, or open the back of your meter (you often have to unscrew them) find the battery, bin it and replace it.

https://www.amazon.co.uk/Beizkna-Multimeter-Contin...

[trickywoo]

I've just tested one and it showed 1.51V

No way 1.7 is correct.

[E-bmw]

They can occasionally get to 1.6 v when brand new & straight out of the pack but never known more than that personally.

Alkaline that is, rechargeable batteries are more like 1.2v

[PelicanHead]

New battery in the multi meter.
Now showing correct readings.

Griffith4ever said:

hehe - no, it should read 1.5v. Your meter battery is dying. Absolutely no way a 1.5v AA would ever read 1.72v. It woudl read 1.499 / 1.5v. (I test them often).

Griffith, hehe back. You are correct, and wrong.
1.72 for a 1.5v aa alkaline would be unusual, granted, but 1.6v or just over is very usual for a fresh 1.5v aa alkaline.

littleredrooster said:

Am I the only one who suspects an over-reading voltmeter here?

littleredrooster was the one that came up with the possibility that my meter may be giving false readings, so kudos to he/she.

E-bmw said:

They can occasionally get to 1.6 v when brand new & straight out of the pack but never known more than that personally.

Alkaline that is, rechargeable batteries are more like 1.2v

E-bmw, correct, that is similar to my reading of 1.615 - 1.616 now.
My nephew's (different model and 'better' than mine) read similar.

I shall return to the battery geezer, remove the leads so they are isolated, ask him to test them again, and, depending on the results, return with one or two batteries.

I have learnt several things regarding testing, also that a multi meter can give a false reading because it's battery is low, and other such interesting stuff.
I will let you know how many batteries I purchase and probably test them, just because I can.

[PelicanHead]

I went back to the battery depot today.
I parked up and disconnected one of the batteries so they were isolated.
In the words of the bloke who tested them, the 2017 battery is f*#@ked and the 2013 battery is really f*#@ked, giving a reading of around 160amps when it is meant to be 600!!
So two batteries were purchased, and at £70 each for 70ah batteries, not bad.

It turns over so fast now that it's a wonder the alternator doesn't fly of it's housing.

Thanks all for the learning curve and passing on your knowledge.

Edited by PelicanHead on Wednesday 19th November 14:43