Agreed that the instrument needs to be calibrated, but the degree of accuracy doesn't need to be NWS grade (IMHO). What you are demonstrating is that the environmental conditions are within the range specified for the test. And if you have enough control you shouldn't be pushing the edges, so it become less critical. Just don't try ESD out in the open on a hot, humid day in the south. Nor try it in the foothills above Denver at any time. The atmospheric pressure will be too low. Remember, the barometer must be calibrated to read "absolute" pressure, not pressure corrected to sea level like the weather guessers will give you.
Ghery S. Pettit -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Brian Oconnell Sent: Monday, December 19, 2011 10:00 AM To: [email protected] Subject: RE: Lab Needed for 17025 Accredited Calibration for Davis Weather Station Transcat will cal stuff that does these parameters and does 17025. RH, temp, and atm pressure xdcrs are common stuff. What is wrong with these cal-lab people? Possible to remove transducers/sensors and send to cal lab to do tables? Most Davis systems are not NWS-grade, and the rated accuracies could allow a company verification process where altitude and temp correction is applied to local METAR data, temp sensor is verified with your recently calibrated instrument used in Type Tests, and the RH sensor can be verified using the chemical kits or calc using dry/wet bulb readings. Do not have a weather station at place of employment, but have several similar sensors connected to data logger to monitor lab conditions during all tests, and have never had any problem submitting this data to auditors. Brian -----Original Message----- > > On 12/19/11, Elliott Mac-FME001 <[email protected]> wrote: >> All >> Our cal guys are telling me that they are having a hard time finding a >> lab that can do 17025 accredited calibrations for our Davis Weather >> Monitor that we use on our OATS to measure temp / humidity / and >> barometric pressure during our testing. >> >> Any suggestions? >> >> Best regards, >> Mac Elliott - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
