I would suggest a wireless approach that consisted of a wired sensor on the paddles with the transmitter located on the paddle shaft above the fluid. Then power the sensor with an energy harvester. The mechanical rotation and the likely vibration should provide enough energy for periodic transmissions. The space above the fluid should be considerably lower temperature. The temperature gradient between the bottom of the shaft and the top of the shaft might also be useable to power the transmitter. You might determine the peak temperature in that area by putting some temperature dots on the top of the shaft. If the actual peak temperature is low enough there some high temperature Lithium cells that may work. Add a centrifugal switch and the sensor would only consume power while in operation. -----Original Message----- From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf Of alan.b.pearce@stfc.ac.uk Sent: Tuesday, March 27, 2018 07:50 To: piclist@mit.edu Subject: RE: [EE]: Temperature sensing - wireless, short range Depending how close the stirrer comes to the side of the bowl, I would consider clipping a thermocouple probe to the top edge and having it run down the inside of the bowl. I'm thinking in terms of a stainless encased probe here, and gently bending it to the profile of the side of the bowl, s= o it shouldn't be more than about 2.5mm high above the bowl lining. For contents at around 200C you will almost certainly need a thermocouple a= s I don't think PRT probes for that temperature are too readily available (yo= u are getting into soldered termination melting realms, so unless the leads are welded they will cause problems). -----Original Message----- From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf Of Brent Brown Sent: 27 March 2018 11:43 To: Microcontroller discussion list - Public. Subject: Re: [EE]: Temperature sensing - wireless, short range Consider, if not considered already, and if remotely possible... reduce the radius of the stirrer and offset it so there becomes room to drop a temperature probe down into the contents. If stirrer really must stir close to or even touch the sides of the vessel then rotate the vessel slowly. -- http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/chang= e your membership options at http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/chang= e your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .