Wikipedia has a pretty good entry:
http://en.wikipedia.org/wiki/Calibration
>From the wiki:
" Calibration is a comparison between measurements b one of known magnitude
or correctness made or set with one device and another measurement made in as
similar a way as possible with a second device.
Also:
"In general use, calibration is often regarded as including the process of
adjusting the output or indication on a measurement instrument to agree with
value of the applied standard, within a specified accuracy. "
and
"For the vast majority of calibrations, the calibration process is actually
the comparison of an unknown to a known and recording the results."
Seems like the terms get used interchangeably, but I'll stand by my statement
that calibration is the comparison process, and adjustment is, well, adjusting
the device. I believe there are entities that can calibrate, but are not
permitted to make adjustments to the devices under test.
Bob
--------------------------------
Bob Spidell - San Jose, CA
on
In my world (Regulated pharmaceutical manufacturing), Calibration is
the process of making adjustments to bring something into tolerance.
Verification is what you are doing to see whether or not the
instrument is within tolerance.
-Paul
On Sat, Mar 5, 2011 at 12:32 PM, Bob Spidell <bspidell@comcast.net> wrote:
> You speak with a great deal of certainly, so I won't dispute that, but the
calibration techniques I'm familiar with measure the wrench's indicated torque
against a calibrated strain gauge (which itself must be calibrated, etc.). I
don't see why you couldn't at least get a calibration card for a beam-style
wrench; e.g. the wrench indicates 50lb-ft, and the strain gauge measures 52,
so you know your wrench reads a bit low in the 50lb-ft range.
>
> To me, 'calibration' means comparing to a known quantity. Adjustment means
bring them into agreement.
>
>
> Bob
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