Dear Jae-Won, I did a lot of Glow Wire tests some years back, and I don't remember there ever being a mathematical formula to calculate the required temperature. The test temperatures were 550, 650, 750, 850 and 760 deg C. Tests were not done using temperatures between these values. I have a 1992 version of the Australian standard and it's highly possible the test procedure is different now.
The higher glow wire temperature is aimed at testing insulation that retains terminals that may become loose and carry greater than 0.5 A. My spec gives examples of connections that may become loose as screw terminals that may be made or remade during installation or servicing. Terminals not considered to be a fire hazard are quick connects and crimped or soldered connections. Insulation supporting this type of terminal is tested at the lower glow wire temperature in section (b). Regards Barry Esmore ---------- > From: [email protected] > To: [email protected] > Subject: Re: Glow-wire Test > Date: Wednesday, 3 June 1998 15:09 > > > Dear Barry > > Thanks for your kind answer. > > I know that Australia standard of glow-wire test. > Because, I have some experience of glow-wire failure > when I requested by test lab. in Australia last year. > > In the IEC 335-1 (third edition) demand tip temperature of glow-wire > 750 centigrade in case of unattended appliance and current exceed 0.5mA. > However, EN and Australia standard want more sever condition as 850. > > You mentioned that the current of connection is the main point to > decide tip temperature. But I do not know what is the correct > mathematics calculation method to choice glow wire tip temperature. > > If you know it, please tell me about. > > Best regards, > > Jae-won Yoo > > > RCIC - http://www.rcic.com > Regulatory Compliance Information Center > > >
