At 12:10 PM 8/14/02 +0000, you wrote:
>Liquid is wine stored in tanks and the range of temp. is from 10 to 30
>degrees.

Be *very* sure that the closed end of the tube is made by TIG welding
or some other NSF* approved (US/Canada standard) or equivalent method.
In particular, you want to avoid cadmium-bearing Ag hard solders which
will look nice, but leach out into the wine and cause contamination. The
inert-gas welded probe is all just plain stainless steel and should
last indefinitely under those conditions, unless damaged physically.

For the heat transfer issue, silicone grease should work, and won't
cause stress on the 18S20.

Personally, I'd specify a proper industrial-quality Pt100 DIN RTD probe
and either use a commercial signal conditioner or make one.

* National Sanitary Foundation  http://www.nsf.org

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
9/11 United we Stand

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