Re: digital devices

2002-05-27 Thread Dan Kwok

If you meant more than 9000 cycles per second, yes, that would be
classified as a digital device under FCC Part 15. SMPS are not likely to
switch at that frequency. More typically, they switch at rates above 30
kHz, well beyond audio frequencies.

-- 

Daniel Kwok, P.Eng.
Principal EMC Engineer 
Intetron Consulting, Inc.  
Vancouver, Canada
Phone (604) 432-9874
Email dk...@intetron.com
Web http://www.intetron.com


Kim Boll Jensen wrote:
 
 Hi all
 
 I have an active loudspeaker which have been using a traditional power
 supply, but will now be using switch mode power supply. Until now it
 have not been under FCC part 15 and ICES 003, as fare as I understand.
 
 Is a switch mode power supply regarded as a digital device according to
 FCC part 15 and ICES 003. It uses timing signals of more that
 9.000/10.000 cycles pr. second.
 
 Best regards,
 
 Kim Boll Jensen
 Bolls Raadgivning
 Denmark

---
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:
 Ron Pickard:  emc-p...@hypercom.com
 Dave Heald:   davehe...@attbi.com

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://ieeepstc.mindcruiser.com/
Click on browse and then emc-pstc mailing list


RE: digital devices

2002-05-27 Thread Robert Wilson

Yes, a switchmode power supply falls under FCC part 15. Also, if by
timing signals you are referring to its switching frequency, I think
you have lost a zero somewhere. No switchmode power supply operates in
the audible frequency range around 9KHz or 10KHz (especially one used to
operate a speaker); you probably meant it operates at 90KHz to 100KHz?

Bob Wilson
TIR Systems Ltd.
Vancouver.

-Original Message-
From: Kim Boll Jensen [mailto:kimb...@post7.tele.dk] 
Sent: May 27, 2002 1:12 AM
To: EMC-PSTC
Subject: digital devices

Hi all

I have an active loudspeaker which have been using a traditional power
supply, but will now be using switch mode power supply. Until now it
have not been under FCC part 15 and ICES 003, as fare as I understand.

Is a switch mode power supply regarded as a digital device according to
FCC part 15 and ICES 003. It uses timing signals of more that
9.000/10.000 cycles pr. second.

Best regards,

Kim Boll Jensen
Bolls Raadgivning
Denmark

---
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:
 Ron Pickard:  emc-p...@hypercom.com
 Dave Heald:   davehe...@attbi.com

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://ieeepstc.mindcruiser.com/
Click on browse and then emc-pstc mailing list