Tony Hwang wrote:

Robert11 wrote:

Hello:

Have been buying a bunch of those standard 9V batteries (a few
different brands) over the past few months, and have noticed that
instead of 9V they have been measuring out, with a VOM, at around 10.0
to 10.25. This is under no load.

Anyone else notice this ?

Was wondering if this might be the cause of all the problems I've been
having with my fire alarms
giving 3 to 4 chirps, around once a day ?

It's probably the same type of chirp signal that the unit gives when
the batteries are low.

Thanks,
Bob

Hi,
How accurate is your meter? Sounds like it is out of calibration.
Clue is different betteries showing same sort of reading.
Hi,
My main bench meter is lab grade calibrated Fluke. I check other meters
against it to see how reasonably accurate it is. I still use old work
horse Simpson 260 on many occasions where low impedance meter input is
needed like on household AC power wiring.