Grace,
The easiest free way is to ask via the KDB website. If what you want to do is
outside the current rules they will tell you.
To change the rules you need money time and a strong stomach. Part 1 of the
Rules section C has the Rule making Procedures, starts with a Petition for
Rulemaking
Lawyers usually do this stuff but no reason why non-lawyer can do it...
best regards
Tom
On Aug 3, 2011, at 11:10 AM, Grace Lin wrote:
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 <tel:240%20401%201388>
________________________________
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 <tel:%2B1%20240%20401%201388>
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.
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]>
-
----------------------------------------------------------------
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]>
