Hi Rich, Thanks for your advice. How can we distinguish the enamel layer for functional, basic and reinforced insulations other than manufacturer's spec?
If the ordinary winding wire insulation is considered as functional insulation only, is there a risk of short circuit in the following scenario. In some windings, there is a thermal device in between. The connecting wires of the thermal device are of the enamel wire of the windings. Normally both the thermal device and the connecting wires are wrapped by insulation tapes together. Is there a risk of short circuit of thermal link in such workmanship if the enamel wire does not have a basic insulation? Regards, Scott On 23/10/12 2:18 PM, "[email protected]" <[email protected]> wrote: > > > > Hi Scott: > > > New, tough materials now allow winding wire insulation to be classed > as basic insulation. Some even qualify as reinforced insulation. > > The new materials usually are comprised of multiple layers. > > IEC 60950 will be revised to accept such insulations as basic or > reinforced after a tough set of qualification tests. Talk to your > winding wire insulation supplier for details. > > Ordinary winding wire insulation is considered functional insulation, > and cannot be relied upon for safety purposes. > > > Best regards, > Rich > > > -----Original Message----- > From: Scott Xe > Sent: Monday, October 22, 2012 10:00 AM > To: [email protected] > Subject: Enamel layer of windings in primary of mains transformer or AC motor > > Is the enamel layer of windings of mains transformer or motor considered as a > basic insulation? Lots of people point out that the primary windings or motor > windings are live part and requires double or reinforced insulation if the > user accessible object could be touch the windings. If the enamel layer is > considered a basic insulation, a supplementary insulation of the a user > accessible object is required. > > Thanks and regards, > > Scott- > - ---------------------------------------------------------------- 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.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. 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]>
