>On Wed, 3 Nov 2004 19:27:57 +0200, Omer YALHI wro= te: >> In our plant we have an industrial oven (not really an oven, but I do= n't >> know the word in English - picture attached) where we melt metals, suc= h as >> bronze, and make the liquid, then the liquid is transferred to another= oven >> where it is kept in liquid form. We would like to be able to measure = the >> temprature of the second oven (where the liquid metal is kept) constan= tly. >> The precision can be between =B110=B0C (if at all possible). >>=20 >> Any ideas how to read the temprature constantly without melting the se= nsor? A device I saw once was a handheld device with a small globe in it. The viewfinder has a split window. You look through it at the crucible, then turn the dial until the brightness of the globe matches the glow of the crucible. Then you read the temp off the calibrated dial. I'm sure the principle can be duplicated electronically. Another way(not sure if it's used) would be to use a temperature gradient. Connect, say, a 1m x 6mm insulated copper rod to the crucible. At the far end you have a chamber that is kept cool with water. If the water is kept at ~40C, and at 10cm towards the furnace you measure 140C, it means the crucible is sitting at ~1040C. There is a time lag, and will have to be calibrated, but should work? Regards Roland Jollivet _______________________________________________ http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist