CISPR 16-4: Uncertainty in EMC Measurements has just been published. This should give you all the ammunition you need to deal with the issue of how to include NSA in your uncertainty budget. If 16-4 is not yet available from the IEC, CISPR/A/355/FDIS is the draft standard upon which it is based. John P. Wagner Regulatory Compliance & Mandatory Standards AVAYA Strategic Standards. 1300 W. 120th Ave, Room B3-D16 Westminster, CO 80234-2726 Phone/Fax: (303) 538-4241 [email protected]
> ---------- > From: [email protected][SMTP:[email protected]] > Reply To: [email protected] > Sent: Wednesday, July 17, 2002 5:43 AM > To: [email protected] > Subject: Re: NSA measurement and its uncertainty > > > KC, > > You don't mention what organization/standard that you are undergoing an > audit with, I'll assume ISO 17025. I think you are correct that it would > be very difficult if not impossible to meet the requirements when you add > in uncertainty that takes into account the receiver, antennas, pre-amp and > such. > > I think you can go about this two ways. The first would be ANSI > C63.4-1992 section 5.4.6.2 it states. > > "The +/- 4 dB tolerance in 5.4.6.1 includes instrumentation calibration > errors, measurement technique errors and errors due to site anomalies." > > The other way is if you are being audited to ISO 17025 section 5.4.6.2 > Note 2. This may be a long shot. I am not an expert in ISO 17025 , but > would mention it. I think that NSA would qualify as a "well-recognized test > method". > > The last thing I would say is that there is currently no requirement by > any governing body for uncertainty to be included in the NSA results. > Technically the governing body is your customer, they define the method > used and how the results are reported. > > Thanks, > > Craig > > > > > [email protected] > > Sent by: To: > [email protected] > owner-emc-pstc@majordo cc: > > mo.ieee.org Subject: NSA measurement > and its uncertainty > > > > > 07/17/2002 03:53 AM > > Please respond to > > kcchan > > > > > > > > > > > Hi all > > I just got a tough question from our auditor about NSA and uncertainty. He > asked if we will include the uncertainty into our Normalized Site > Attenuation measurement or not. > > If we include the uncertainty of NSA measurement, it is impossible for us > to ensure it is within the +/- 4dB with 95% CL. > > I would like to seek comment form the expertise if it is necessary to > include the uncertainty when we do the NSA measurement. > > Thank you > KC Chan > > > ------------------------------------------- > 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: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: [email protected] > Dave Heald: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > Jim Bacher: [email protected] > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" > > > > > ------------------------------------------- > 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: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Ron Pickard: [email protected] > Dave Heald: [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > Jim Bacher: [email protected] > > All emc-pstc postings are archived and searchable on the web at: > http://ieeepstc.mindcruiser.com/ > Click on "browse" and then "emc-pstc mailing list" >
