Weather Banter - View Single Post - need a temperature sensor with .1 degree accuracy

Rich Webb

On 15 Oct 2005 00:36:49 -0700, wrote:

This is getting, confusing, complex and interesting!

In the same line as the Omega hint, and in the same cole palmer
catalog, I saw a Digi-sense Digital Handheld thermistor thermometer,
which has range of -40 to +125 Degree C and claims accuracy of +- 0.2
Degree C. Also offers an optional probe. Now is there any fine print
here?

Don't assume that marketing copy writers understand the differences
between "digits displayed to the right of the decimal point" and
"precision" and "accuracy."

As a minimum, read the manufacturer's datasheet, not a blurb on a web
page. If they are indeed making an assertion with respect to absolute
accuracy then I would expect to see:

A number for the instrument's accuracy as a standard deviation or a
statement that the stated accuracy is +/- so many std devs. There should
be a statement regarding operating and/or environmental limits.

AND a statement that the instrument calibration is traceable to a
standard maintained by NIST or an equivalent national standards bureau.

AND a signed and dated seal on the instrument (preferred), or a
similarly signed and dated document with the instrument's serial number,
stating by whom and when it was last calibrated and including a graph or
table showing the residuals between the measurements of that instrument
and a maintained standard throughout the instrument's range.

Absent all three of those, any claimed "accuracy" is, at best, a dumb
mistake by the English major who wrote the blurb and, at worst, a
deliberate attempt to mislead the customer.

--
Rich Webb Norfolk, VA