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Wild_Bill Wild_Bill is offline
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Default digital caliper fault

I would also recommend that digital caliper owners use silver oxide SR44
cells.

Another potential problem could be the battery/cell contacts in the reader
head. They need to be very clean, not "scrape the plating off" clean, but
clean.

Additionally, I routinely rub coin and button cells on a clean piece of
paper (white printer paper is fine) to rub any surface contamination or
oxidation off, when I take them out of their package.

The OP's symptoms were exactly what I experienced when using the alkaline
cells.. moving the head too fast caused missed counts.
None of that has happened since I started using silver oxide cells.

I keep taking the cell out of digital calipers when I put the caliper back
in it's box, because the circuit will eventually drain the cell while the
caliper isn't being used (on many models even if the off button is pushed),
which will likely cause the cell to leak if it goes completely dead.

I keep wanting to add an on/off switch (a tiny one from a mini LED keychain
light) but still haven't gotten rountuit.

--
WB
..........


"DoN. Nichols" wrote in message
...
On 2010-02-22, Jordan wrote:
My cheap electronic calipers have started playing up. If I move it too
quickly, it reads wrong. If moved slowly it seems OK, but that's not
very reassuring. Are these things total junk to be avoided, or just I
got a bad'un? New battery didn't help.


O.K. What new battery (cell) did you use? These typically take
the LR44/SR357 type cells, and there are Alkaline versions which don't
put out as much voltage. Make sure that it is a true SR357 and see what
happens.

Also -- try washing any accumulated oil and coolant off the
cloth/plastic face of the bar. These work by capacitive connection to
patterns in the bar under the covering, and accumulation of things which
will at least partially conduct electricity (or even change the
dialectric constant) can keep them from working right.

The behvior of yours is typical to what I see with tired cells,
but I haven't personally experienced the buildup of grunge yet so I
don't know what it is like.

Enjoy,
DoN.

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