Thanks to everyone for the replies!!! Although UL1950 requires the 125% rule (80% of breaker), at high ambients, the tables in 310-17 are worst case..... thanks for all your view points.
Thanks again!!! Kelly At 09:12 AM 3/10/00 -0600, [email protected] wrote: > > > >Kelly: >The NEC is written to keep structures safe. Flexible cords used in structures >are normally used in free air. >If you are using a flexible cord in equipment, you need to rate its ampacity in >accordance with whatever standard you are using. The NEC relies on the NRTL >label and testing for the safety of equipment. >If you are using a flexible cord in a high ambient I would contact the mfg for >the appropriate derating. > > > > >Kelly Tsudama <[email protected]> on 03/09/2000 09:33:14 PM > >Please respond to Kelly Tsudama <[email protected]> > >To: [email protected] >cc: (bcc: Ed Rauch/MAIN/MC1) > >Subject: Correction factor for power supply cords. > > > > > > >Hi Group > >I am hoping that I can get your opinions with an issue regarding the correction >factor of power supply cords. For instance, in the NEC table 310-17, for >single >conductors in free air, there is a chart at the bottom of the table that allows >you to determine how to factor in the ambient temperature. However, for a >flexible power cord, the table 400-5 does not have any correction factor table. > >At first I thought that this is because cords always have a temperature rating >marked on them, but then I recall that most (if not all) single conductors have >this marking too.... Is there a need to "de-rate" a power cord's current rating >based on the expected ambient temperature? If so, where in the NEC did I miss >this fact? If not, why not? > >Thanks for your help, >Kelly > >**************************************************************** >Kelly Tsudama >Cisco Systems >[email protected] >408-527-0216 >408-525-9150 fax >408-322-9024 pager > >------------------------------------------- >This message is from the IEEE EMC Society Product Safety >Technical Committee emc-pstc discussion list. > >To cancel your subscription, send mail to: > [email protected] >with the single line: > unsubscribe emc-pstc > >For help, send mail to the list administrators: > Jim Bacher: [email protected] > Michael Garretson: [email protected] > >For policy questions, send mail to: > Richard Nute: [email protected] > > > > > > > > > >------------------------------------------- >This message is from the IEEE EMC Society Product Safety >Technical Committee emc-pstc discussion list. > >To cancel your subscription, send mail to: > [email protected] >with the single line: > unsubscribe emc-pstc > >For help, send mail to the list administrators: > Jim Bacher: [email protected] > Michael Garretson: [email protected] > >For policy questions, send mail to: > Richard Nute: [email protected] > **************************************************************** Kelly Tsudama Cisco Systems [email protected] 408-527-0216 408-525-9150 fax 408-322-9024 pager ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Jim Bacher: [email protected] Michael Garretson: [email protected] For policy questions, send mail to: Richard Nute: [email protected]
