Hi Robert, Recently, I bought several similar heaters for my home. I recall reading in the operation instructions, explicit safety warnings against using extension cords with the heater. Was the extension cord supplied with the heater?
--------------------------------------------------------------------- Dan Kwok, P.Eng. Principal Engineer Electromagnetic Compatibility Intetron Consulting, Inc. Ph (604) 432-9874 E-mail [email protected] Internet http://www.intetron.com ----- Original Message ----- From: "Robert Macy" <[email protected]> To: "Roman, Dan" <[email protected]>; <[email protected]> Sent: Thursday, October 25, 2001 8:49 AM Subject: Re: skinny power cords. > > Just have to jump in here with personal experience: > > In our bedroom we have a deLonghi radiator heater which uses an extension > cord (high cost UL approved) heavy guage #12 wire to power it - when it's > used. This extension cord plugs into a "multi outlet" adapter, also heavy > duty UL approved. At the time of the incident there was no power being used > from this outlet. > > I was in another room, my wife was sitting on the edge of the bed watching a > news blurb on TV when she heard a funny sound, a scritch, scritch. She > called to me to come listen. Scritch, scritch, scritch got louder. As I > arrived, flames started lapping up the wall from the outlet while still > making arcing sounds. The flames were less than 6 inches from curtains. I > reached into all this and unplugged the extension cord which luckily stopped > the fireworks display. Imagine, if we had not been there. > > Upon examination, it appeared that an arc had formed between the blades of > the extension cord (remember no power at the time). That arc was not > sufficient to drop the 15A breaker to the outlet, yet was sufficient to > carbonize the UL approved material which further sustained the arc. > > I posted this to the newsgroup alt.home.repair where a fireman jumped in > describing how this exact mechanism is what starts most home fires! Isn't > that an encouraging thought! > > Anyway, a little damn fuse in the plug would not have helped in this > circumstance, complete waste of time, much like the main breaker was. > > - Robert - > > Robert A. Macy, PE [email protected] > 408 286 3985 fx 408 297 9121 > AJM International Electronics Consultants > 619 North First St, San Jose, CA 95112 > > -----Original Message----- > From: Roman, Dan <[email protected]> > To: [email protected] <[email protected]> > Date: Thursday, October 25, 2001 7:41 AM > Subject: RE: skinny power cords. > > > > > >I agreed completely with Scott. A 6 to 9 foot 18AWG cord will handle well > >in excess of 20A for a short period of time without starting to smoke > (heck, > >it'll handle close to in excess of 60A for a very very short time without > >bursting into flames--not that it was a good experience finding this out). > >Point is, the cordage will handle a fault either indefinitely or long > enough > >for the branch circuit breaker to trip provided you are connected to a 15A > >or 20A branch circuit. > > > >Another data point, you routinely pass more current through the cord when > >doing the earthing test and that uses more current than the cord is rated. > >Leave the tester on for awhile and the cord does not really heat up either. > > > >What this list needs is a power cord manufacturer or agency safety engineer > >that does power cords to settle this once and for all! > > > >Dan > > > >-----Original Message----- > >From: Scott Lacey [mailto:[email protected]] > >Sent: Wednesday, October 24, 2001 7:43 PM > >To: Gary McInturff > >Cc: [email protected] > >Subject: RE: skinny power cords. > > > > > > > >Gary, > >I believe the answer is that the power cord rating of 6 or 10 amps is the > >operating current, at which it will have minimum temperature rise. Under > >fault conditions it will experience a rather dramatic temperature rise that > >is still well below the melting temperature of the insulation. The breaker > >or fuse should clear well before the cord is "cooked" to the point of > >failure. > > > >Scott Lacey > > > > > > ------------------------------------------- > 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: > [email protected] > with the single line: > unsubscribe emc-pstc > > For help, send mail to the list administrators: > Michael Garretson: [email protected] > Dave Heald [email protected] > > For policy questions, send mail to: > Richard Nute: [email protected] > Jim Bacher: [email protected] > > All emc-pstc postings are archived and searchable on the web at: > No longer online until our new server is brought online and the old messages are imported into the new server. > ------------------------------------------- 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: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Michael Garretson: [email protected] Dave Heald [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: No longer online until our new server is brought online and the old messages are imported into the new server.
