On Tue, 30 Jul 2019 at 07:03, Frank Stellmach <[email protected]> wrote:
> // My serial number is: MY45044988 > > Hi Miguel, > > So it's now nearly 10 years old, and you should definitely save the > content of the CALRAM, and maybe already change the DALLAS chips. These > might last another 5 years, but nobody can make sure. If it has been > used for 7-8 years, maybe w/o calibration, its LTZ1000A reference has > already drifted a lot, so a calibration is required.. > > Also the LTZ1000A reference might need some time to recover, because it > might show some hysteresis or rush-in effect after 2 years storage. How long should he run it continuously to recover? Before sending it for calibration? If you want to get a proper calibration anyhow, you may also set the > oven temperature lower, to 65°C as explained, and then send it out for > calibration. Or if you already have a stable external reference, you can > preliminarily copy the calibration after changing the oven. How long should he run it continuously after changing the oven temperature? I am guessing, (perhaps incorrectly), that there’s no point running it continuously before changing the oven temperature if he intends changing the oven temperature. I’ve known Miguel for quite a few years - only by the Internet. I have never met him in person. He doesn’t have access to any any stable references, and I don’t think he would want to run air conditioning 24/7. He can tell you how much the temperature varies throughout the year, if he has logged it, which I doubt. Being in Mexico, I don’t think there will be any local time nuts. I personally think that he would be better getting the meter calibrated in the USA rather than Mexico. He had been told it can be calibrated in Mexico, but it would have to go to the USA to have the firmware upgraded! From a number of things he has told me about Mexico over the years, I personally would not want to get anything done there. > > Frank Dave -- Dr. David Kirkby, _______________________________________________ volt-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/volt-nuts_lists.febo.com and follow the instructions there.
