I worked in the food service industry for a while making grill timers,=20 etc. One of the temp sensors we used was a thermistor in a small glass diode=20 package inserted into a long thin SS tube and potted. Kids in Mc used to have sword fights with them....:-) Mark Skeels Engineer Competition Electronics, Inc. TEL: 815-874-8001 FAX: 815-874-8181 www.competitionelectronics.com On 10/19/2010 3:20 PM, Marc Nicholas wrote: > On Tue, Oct 19, 2010 at 3:17 PM, alan smith wrote: >> thanks for the responses...i've forwarded these sites to my client for h= is review. When you said you have had better luck with RTD's over thermoco= uples, can you explain what your experiences were? RTD's are generally les= s expensive, but are they as stable as a thermocouple? > I just temperature compensated my RTD and was able to achieve decent > resolution and accuracy with a simple voltage divider. My application > was also food services (prototype cooking machine). > > There are also differential AtoD reference designs for RTDs, but I > didn't find that beneficial in my application. > > How accurate do you need the probe to be? I'd be surprised to hear of > anything requiring accuracy of more than 0.2c in the food service > industry. > > -marc > --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .