I've been told back when I did TCB work, if a spectrum holder/owner complains, they get attention, or if there are public complains, the FCC will look into it. If it can be demonstrated that there is a problem not already addressed by the regulations, they will consider it. To add an exempted device that has not needed FCC regulations for the last 30 plus years would take a very large lobby, as in $$$. But come up with a new technology, one that has significant potential for causing interference, and they are all over it. For example software defined radios. Also, the FCC has changed over the years from approvals and certifications to enforcement. It's much easier and fun to chase bad guys than chasing paperwork. So show the FCC the bad guy, the interference, and they'll work on it.
Attitude is Mind over Matter. If you don't Mind, it doesn't Matter... This email has been displayed using 100% recycled electrons and 100% pure virgin photons. ________________________________ From: Grace Lin <[email protected]> To: Thomas Cokenias <[email protected]> Cc: [email protected]; [email protected] Sent: Wednesday, August 3, 2011 2:10 PM Subject: Re: [PSES] FCC Exempted Devices Tom, Thank you very much for seconding Mike's comments. How easy/difficult to have FCC add exempted devices? How and where to start? Best regards, Grace 2011/8/3 Thomas Cokenias <[email protected]> Hi Grace I was working at the FCC lab at the time (Mike is just a kid compared to me) and that's pretty much the thinking that was going on. best regards Tom Cokenias T.N. Cokenias Consulting P.O. Box 1086 El Granada CA 94018 On Aug 3, 2011, at 9:37 AM, Mike Violette wrote: Hi Grace, Good to hear from you, too. I think the FCC exempted appliances because during the original incarnation of the Rules (Docket 20780 circa 1979—yes, I am dating myself) there was scant idea that microprocessors would be so widely dispersed and installed in almost any device imaginable. Also, the appliance manufacturers (as well as the vehicle and medical device folks) had a strong influence on the manufacturers. I don’t think it had anything to do to reduce lab operators’ capital outlay, but rather the economics favoring the exempted industries. Just a notion. Mike Violette [email protected] Washington Laboratories & American Certification Body Radio Frequency, Electrical Safety & Wireless Cell: 240 401 1388 ________________________________ From: Grace Lin [mailto:[email protected]] Sent: Wednesday, August 03, 2011 10:53 AM To: [email protected] Subject: Re: [PSES] FCC Exempted Devices Good Morning, Mike, It is good to hear from you. I would like to share with you and members my findings/thoughts, based on some measurement I took lately. Turning on and off relays with 16A/heavy load (high current?) creates big spikes (clicks). The amplitude of the spikes does not comply with FCC §15.107 conducted emission limits (for continuous disturbance?). Turning on and off relays without load creates much smaller spikes (clicks). The amplitude of the spikes complies with FCC §15.107 conducted emission limits (with good margins). Most of household appliances are high curent devices. CISPR 14-1 / EN 55014-1 gives relaxation for click noise. In order to apply for the relaxation, click rate must be measured. Most of spectrum analyzers, from my understanding, have no capability to measure click rate. R&S has a free download software, "Click Rate Analyzer", for its certain models of the EMI receivers wtih FFT option (a +$8,000 option). My guess is: FCC exempts appliances in order not to increase labs' (tax payers') financial burden. Agree? If you agree with my thoughts, here is my question: should a 16A load device with relays be exempted? Thank you very much for sharing your comments. Best regards, Grace Lin On Wed, Aug 3, 2011 at 10:06 AM, Mike Violette <[email protected]> wrote: The appliance manufacturers had an effective lobbying campaign when the rules were written! Mike Violette Washington Laboratories & American Certification Body [email protected] +1 240 401 1388 On Aug 3, 2011, at 9:39 AM, Grace Lin wrote: Dear Members, Does anyone know the reason FCC exempts devices listed under FCC §15.103(d) as quoted below? “(d) A digital device utilized exclusively in an appliance, e.g., microwave over, dishwasher, clothes dryer, air conditioner (central or window), etc.” FCC KDB 772105 clarify the exempted household appliances: “Exempt household appliances are electrical machines intended for household tasks that assist persons in washing and drying clothes, household cleaning, cooking, or food preparation; or is equipment that is directly involved in conditioning the supply of household water and air (heating, cooling and humidifying) in a residence. This includes appliances such as a vacuum cleaner, washing machine, dishwasher, clothes dryer, air conditioner (central or window), etc. This exemption is limited to basic housekeeping appliances and is not intended to apply to all home-use products that may contain digital logic.” I wonder (and would like to learn from members) if the exemption is due to the discontinous disturbance as stated in the EN 55014-1 (CISPR 14-1), the emission requirements for household appliances in the EU. I list several paragraphs excerpted from CISPR 14-1: 2005 for reference: “Switching operations in thermostatically controlled appliances, automatic programme controlled machines and other electrically controlled or operated appliances generate discontinuous disturbance. The subjective effect of discontinuous disturbance varies with repetition rate and amplitude in audio and video presentation. Therefore distinction is made between various kinds of discontinuous disturbance. “(CISPR 14-1 Clause 4.2) “The limits for discontinuous disturbance depend mainly on the character of the disturbance and on the click rate N .....” (CISPR 14-1 Clause 4.2.1) “For discontinuous disturbance, the click limit Lq is attained by increasing the relevant limit L (as given in 4.1.1) with: 44 dB for N<0.2, or 20 lg (30/N) dB for 0.2≤N<30 “ Thank you very much for your time and look forward to your comments. Best regards, Grace Lin - ---------------------------------------------------------------- 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://product-compliance.oc.ieee.org/ Graphics (in well-used formats), large files, etc. can be posted to that URL. 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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://product-compliance.oc.ieee.org/ Graphics (in well-used formats), large files, etc. can be posted to that URL. 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://product-compliance.oc.ieee.org/ Graphics (in well-used formats), large files, etc. can be posted to that URL. 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]>
