I would add that if your power source puts out milliwatts and has a high source impedance such that attempting to draw more than design current causes foldback or just plain loading then even if there is a high voltage section it will be even more current limited and is therefore not in the same class from a safety point of view as a high voltage section developed directly off the mains.
---------- >From: "Robert Wilson" <robert_wil...@tirsys.com> >To: "Ron Pickard" <rpick...@hypercom.com>, <emc-p...@majordomo.ieee.org> >Subject: RE: IEC 60950 & Solar Cells >Date: Fri, Jun 7, 2002, 10:49 AM > > > On the surface, it seems to me that that requiring any sort of > regulatory compliance for a device operating from a 3 Volt source would > be utterly absurd. But then, from my perspective, regulatory agencies > are not always noted for their use of common sense in creating their > regulations. The fact that solar cells are used as a power source should > be irrelevant. There would be no functional difference between operating > from a 3V battery and a 3V solar cell. > > The only reason I could imagine that regulatory controls could extend > their all-controlling tentacles into this issue is if the 3 Volt source > was internally converted into much higher voltages, or you are > generating potential EMI. But that, too has nothing to do with the > product using solar cells. > > Bob Wilson > TIR Systems Ltd. > Vancouver. > > -----Original Message----- > From: Ron Pickard [mailto:rpick...@hypercom.com] > Sent: June 6, 2002 3:26 PM > To: emc-p...@majordomo.ieee.org > Subject: IEC 60950 & Solar Cells > > > To all, > > First, a little background. > I have been asked a question that I did not know the answer to, which > relates to a potential new > product. As I understand it, this device will be relatively small, > consume very little power and > will only display particular information depending on the application. > What I have been told, this > device will be powered by a solar cell with a potential 3V coin battery > for back up (the battery > part is iffy). I can't give anymore information about it because I don't > know any more. > > Now, to the questions. > As the scope of IEC 60950 3rd Edition or IEC 60950-1 applies to > equipment that is powered "up to" > 600V", it would seem that the standard would apply to this product. > However, I cannot find a single > reference to a solar cell energy source. Would a solar cell energy > source be treated similarly to a > battery? Would this small LCD display device even be required to be > evaluated to IEC 60950 3rd > Edition or to IEC 60950-1? > > As always, I look forward to your insightful replies. > > Best regards, > > Ron Pickard > rpick...@hypercom.com > > > > ------------------------------------------- > 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" > > ------------------------------------------- > 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" > ------------------------------------------- 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"
