Hello Chris,
The answer is +55C, as later versions of GR-63 define shelves as 36” in height or less. Shelves are tested to +55C short term. But that is not the total solution to your problem, the GR-63 you are referencing is several revisions obsolete. You will need GR-63-CORE Issue 3, March 2006. There are many clarifications and new thermal requirements that must be met compared to the 1995 version of GR-63. They include the clarification for your original question and many criteria relating to thermal margins, fan failures and a reorganized thermal cycle. I am not aware of any service providers that would accept the 1995 GR-63 for conformance testing. Also the testing must be performed by an appropriately accredited lab based on the requirements of your particular customer. These accredited labs will be using the newest GR-63 and testing to these revised criteria. As an FYI, the specific answer to your question can be found in note 1 of Table 4-4 and the second bullet item of section 5.1. Hope this helps, Jim Jim Wiese NEBS Project Manager/Senior Compliance Engineer ADTRAN, Inc. 901 Explorer Blvd. Huntsville, AL 35806 256-963-8431 256-714-5882 (cell) 256-963-6218 (fax) [email protected] ________________________________ From: [email protected] [mailto:[email protected]] On Behalf Of Chris Sent: Tuesday, May 27, 2008 1:49 PM To: emc-pstc Cc: Christopher Saleem Subject: NEBS operating temperature cycle criteria GR-63 Folks I have a question regarding NEBS operating temperature duration for our NEBS experts. Operating and humidity criteria R4-7 GR-63 issue 1, October 1995. 1. shows 50C @ 32%RH dwell for 12 hours and 2. 50C @ 15%RH dwell for 4hrs * 55C for equipment shelves that fill less than half the frame (length). Our equipment is 25 inches in length (depth) and 17 inches wide and height is 3.5 inches. My question is do we have to operate at 50C for 16 hours or *55C for 16 hours? We trying to design maximize cooling efficiency to keep appliance temp from exceeding chip set manafacturers specification. thanks in advance for your help. Christopher - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
