I wrote:
On Fri, Dec 9, 2011 at 12:59 PM, Jed Rothwell <[email protected]> wrote: > Peter Heckert <[email protected]> wrote: > > The thermoelement on the tape has a bad contact to the metal and measures >> preferrably the air temperature. >> > > This is not a valid test. You have to cover up the thermocouples. Rossi > did not leave them open to the air. > > Of course leaving them open will pick up the air temperature. That is > obvious. Yesterday when I removed the foam pipe insulation, the temperature > dropped 1.4 to 3°C, even though the TC was still covered with adhesive > tape. It began fluctuating, no doubt due to air currents. > > Putting a layer of tape under the TC in open air might well increase this > problem. You have put everything under insulation. > > > I see no point to testing for problems that Rossi cannot possibly have. > In other words, there might be a 0.1 mm gap, even though the TC are under tightly wrapped insulation. It is possible that some of the threads from insulation are between the TC and the metal, and maybe that causes a problem. I would be happy to do a test for this. I can clip some insulation, put it under adhesive tape on the metal surface, and put the TC on top of that. That should test both hypotheses at the same time. I would use a metal cup for this, filled with hot water, with the TCs on the outside. I do not have a nifty metal heater. As I said, you have to put insulation over the whole thing or the test is meaningless. - Jed
