John, ----- Original Message ----- From: "John Woodgate" <[email protected]>
>>I don't know. I'm asking you, experts here. > > I know that you don't, but some of the guys here probably had a hand in > writing that text, so know what they meant it to mean. > That is why I have written experts and not expert ;-) > The advice you were given about not using a PTC thermistor seems to be > wrong. Clause 2.5, item b) of IEC/EN 60950-1:2006 allows the use of a PTC > complying with selected requirements of IEC 60730-1. It is easier for me to find the fuse with approvals I think I understand than PTC which is specified to comply with this IEC (not sure but probably I have never seen in PTC datasheet such information). > The simplest practical solution for your 12 V 0.3 A product is to sell the > power supply with it. That way, you have provided an LPS. There are many power supplies for use with our devices. It depends on how many devices are in specific installation the smaller or bigger supply is used by the installer. It depends on how long it is expected to work when power is off the supply is selected with smaller or bigger accu in it. There is no sense to transport (CO2 emission) all these kg to us and then to installer who probably can buy it in the next street shop. As I understand it the other problem is that if you just have in your offer some power supply this not solves the LPS problem, but when you sell your device as a set with somebody's power supply you become responsible for the whole set, so ..... > If you can't do that, for some reason, then specify an LPS in the > instructions and, if possible, label the power connector '12 V 0.3 A LPS > source'. And we came back to this thread beginning ;-) Best Regards Piotr Galka - 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://www.ieeecommunities.org/emc-pstc 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]>
