As I understand it the interpretation to have tracibility to your national authority through equipment used only for calibration originated with NAMAS. Some other accreditors have picked it up since then.
The requirement need not be that onerous. You can calibrate your own equipment traceably to your national authority using equipment that you send out for calibration. Where the instrument is cheap (multimeter) we buy an extra and use it only for calibration. Where it is expensive (oscope, receiver), we use it for calibration only directly after it returns from outside calibration (or inside tracible cal) and after we have calibrated our secondary equipment with it we put it into regular service for the year. If you manage your yearly calibration cycle well this shouldn't crimp your style too much. The key is not to have equipment in your calibration chain back to the national authority that has been used for non-calibration purposes between the time of its calibration and that of the secondary calibration. The idea is to have high confidence that the tracibilty chain is intact. If a piece of equipment in the chain has been used daily in regular rough and tumble testing it is seen as having a much higher probability of operating outside of its tolerances. In my experience the outside cal houses are pretty tough on their gear too, so I am not sure that much is gained. I personally think this interpretation is overly severe, but we comply with it because we want our test reports to be accepted by authorities who think this process is reasonable. To directly answer your specific question about a signal generator used in immunity: If it is being used as an uncalibrated signal source in the measurement and you are using a power meter or receiver for tracibility then you can use that signal generator, even if it went off a cliff the day before. If you are relying on the calibrated output level that the signal generator says it is putting out, then you should not have used that instrument in non-calibration use since its last calibration. Jon. "Flinders, Randall" wrote: > Does this mean that a signal generator that is used for Radiated > Immunity testing should not be used to calibrate Pre-Amps and Cables? > How about Antenna Calibration? Can you use the same receiver you use on > the OATS to calibrate those? I know this is a common practice with > Commercial Test Labs. > > Is there guidance as to what types of equipment can be used for both lab > use and for the calibration of other equipment? > > michael.sundst...@nokia.com wrote: > > > > I think there is a special requirement to keep the calibration equipment > > separate from the EMC equipment. In other words the calibration equipment > > can only be used for the calibration process and not for testing EMC. > > > > > Michael Sundstrom > > > Product Test Technician EMC > > > Nokia Mobile Phones, Dallas PCC > > > > > > * Email michael.sundst...@nokia.com > > > % Desk (972) 374-1462 > > > *Mobile (817) 917-5021 > > > * Fax (972) 374-0901 > > amateur call: KB5UKT > > > > ------------------------------------------- > > This message is from the IEEE EMC Society Product Safety > > Technical Committee emc-pstc discussion list. > > > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > > > To cancel your subscription, send mail to: > > majord...@ieee.org > > with the single line: > > unsubscribe emc-pstc > > > > For help, send mail to the list administrators: > > Michael Garretson: pstc_ad...@garretson.org > > Dave Heald davehe...@mediaone.net > > > > For policy questions, send mail to: > > Richard Nute: ri...@ieee.org > > Jim Bacher: j.bac...@ieee.org > > > > All emc-pstc postings are archived and searchable on the web at: > > http://www.rcic.com/ click on "Virtual Conference Hall," > > ------------------------------------------- > This message is from the IEEE EMC Society Product Safety > Technical Committee emc-pstc discussion list. > > Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ > > To cancel your subscription, send mail to: > majord...@ieee.org > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson: pstc_ad...@garretson.org > Dave Heald davehe...@mediaone.net > > For policy questions, send mail to: > Richard Nute: ri...@ieee.org > Jim Bacher: j.bac...@ieee.org > > All emc-pstc postings are archived and searchable on the web at: > http://www.rcic.com/ click on "Virtual Conference Hall," -- Jon D. Curtis, P.E. Director of Engineering Curtis-Straus LLC One Stop Laboratory for NEBS, EMC, Product Safety, and Telecom Testing. 527 Great Road Littleton, MA 01460 USA Voice 978-486-8880 Fax 978-486-8828 email: jcur...@curtis-straus.com WWW.CURTIS-STRAUS.COM ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: pstc_ad...@garretson.org Dave Heald davehe...@mediaone.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.rcic.com/ click on "Virtual Conference Hall,"
