Hello all,
I'm writing some guidance on Class A vs Class B and I was thinking about the Why. As in why do we separate emissions into Class A and B? Reasons I've heard (which make some kind of sense even if I've not actually looked into the figures) include: a. Concentration of electronic equipment - domestic premises are more likely to have other interference equipment operating in closer proximity to receivers than in a commercial/industrial environment. b. Quantity of devices sold - consumer devices used in a domestic sphere have a much higher sales volume c. Nature of installation - Class A equipment installed by more technically competent users, Class B installed by less knowledgeable users. Does anyone have any additional justification, historical perspective, or can point me in the direction of a standard that describes this in more detail? I've looked in IEC TR 61000-2-5 which, although it mostly focuses on immunity, mentions these above reasons. CISPR 16-4-4 seems to deal with statistical methods. IEC TR 61000-1-1 deals in general terms with the concept of a margin between Emissions and Immunity. But no definitions for the derivation of these Classes. Thanks in advance! All the best James James Pawson Managing Director & EMC Problem Solver Unit 3 Compliance Ltd EMC : Environmental & Vibration : Electrical Safety : CE & UKCA : Consultancy <http://www.unit3compliance.co.uk/> www.unit3compliance.co.uk | <mailto:ja...@unit3compliance.co.uk> ja...@unit3compliance.co.uk +44(0)1274 911747 | +44(0)7811 139957 2 Wellington Business Park, New Lane, Bradford, BD4 8AL Registered in England and Wales # 10574298 Office hours: Every morning my full attention is on consultancy, testing, and troubleshooting activities for our customers' projects. I'm contactable between 1300h to 1730h from Monday to Friday. For inquiries, bookings, and testing updates please send us an email on <mailto:he...@unit3compliance.co.uk> he...@unit3compliance.co.uk or call 01274 911747. Our lead times for testing and consultancy are typically 4-5 weeks. -- This email has been checked for viruses by AVG antivirus software. www.avg.com - ---------------------------------------------------------------- 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 EMC-PSTC@LISTSERV.IEEE.ORG All emc-pstc postings are archived and searchable on the web at: https://www.mail-archive.com/emc-pstc@listserv.ieee.org/ Website: https://ewh.ieee.org/soc/pses/ Instructions: https://ewh.ieee.org/soc/pses/list.html (including how to unsubscribe) List rules: https://ewh.ieee.org/soc/pses/listrules.html For help, send mail to the list administrators: Mike Sherman at: msherma...@comcast.net Rick Linford at: linf...@ieee.org For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> _________________________________________________ To unsubscribe from the EMC-PSTC list, click the following link: https://listserv.ieee.org/cgi-bin/wa?SUBED1=EMC-PSTC&A=1
