> ------------------------------ > > Date: Mon, 18 Aug 2008 06:19:02 EDT > From: Frank Condelli <RAlanen@AOL.COM> > Subject: Re: Dometic Fridge propane operation stuff > > > ...First time I ever hear of a Thermocouple that generates electricity ! > They all do Frank, that's how they work! Same thing that causes galvanic corrosion, you have two different metals fused at the measurement junction, and if that junction is at a higher, or lower, temperature than the other ends of the wires, you generate a voltage (in the millivolt range). Biggest problem with TC's is that the voltage generated is proportional to the temperature *differential* between the measurement junction (TC tip) and the Meter (cold junction), so you still need to be able to measure what the cold junction temp is to get an actual temperature. In the fridge use, however, this is not a problem, since all you want to know is whether the heat chamber is significantly higher in temp than the cold junction, not what the actual temp is. TC's great for that since you can use the millivolt signal to trip your circuit, or use in a comparator. Cheers, Keith Hughes '86 Westy Tiico (Marvin) |
Please note - During the past 17 years of operation, several gigabytes of
Vanagon mail messages have been archived. Searching the entire collection
will take up to five minutes to complete. Please be patient!
Return to the archives @ gerry.vanagon.com
The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.
Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.