That's what I love about this mailing list. I learn something new most every day. Thanks Tania!
---------- From: Grant, Tania (Tania) [SMTP:tgr...@lucent.com] Sent: Wednesday, March 10, 1999 4:27 PM To: 'EMC-PSTC - forum'; 'WOODS, RICHARD' Subject: RE: Rack System Safety (UL1950/EN 60950) Questions Richard, Regarding your last statement "....I don't believe that they [CSA & UL] will accept each others marks." Certain UL and CSA component standards have been "harmonized" and, I believe, this effort is continuing. If you look at Appendix P.2 [be sure it is P.2 and not P.1] of UL 1950, 3rd edition, you will find a matrix of UL and CSA component standards where meeting one or the other is considered acceptable for meeting the requirements of UL1950, 3rd edition. Additionally, if you are working with an astute UL engineer, very often they will inform you of additional components that fall under that category but have not yet been published in this Appendix. Tania Grant, Lucent Technologies, Octel Messaging Division tgr...@lucent.com ---------- From: WOODS, RICHARD[SMTP:wo...@sensormatic.com] Sent: Wednesday, March 10, 1999 5:00 AM To: 'EMC-PSTC - forum' Subject: RE: Rack System Safety (UL1950/EN 60950) Questions As I think about this situation, there is a way of obtaining UL Listing on the rack and have other certification marks on the internal equipment. Have UL List just the rack without the equipment. Now you can mix and match the internal certified equipment as you see fit keeping in mind not to exceed the cooling and electrical capacity of the rack. This is what we use to do a decade ago at a mini-computer company. We would configure systems from Listed racks, cpus, disks, tapes, etc. Now to Jim's point. There is no law that requires one agency to accept the certification marks of another agency. For example, UL will not accept ETL marks on components and both are NRTLS. The only way one agency will accept the marks of another is if there is an agreement between them. The CB scheme is one good example. CSA and UL have an agreement to accept each others test data I believe, but I don't believe that they will accept each others marks. ---------- From: Jim Eichner [SMTP:jeich...@statpower.com] Sent: Tuesday, March 09, 1999 3:23 PM To: 'EMC-PSTC - forum' Subject: RE: Rack System Safety (UL1950/EN 60950) Questions Re Richard's item 5)... > 5. UL requires that all internal equipment be UL Listed or > Recognized. > If that is true, then the value of the CSA/NRTL mark, and conversely the cUL mark if CSA plays this way too, is highly questionable. Do you have a direct-from-UL interpretation saying that they are not accepting the CSA/NRTL mark? If so, I would expect CSA to take action to defend its mark, and UL to have no firm ground to stand on! Comments? Jim Eichner Statpower Technologies Corporation jeich...@statpower.com http://www.statpower.com Any opinions expressed are those of my invisible friend, who really exists. Honest. > -----Original Message----- > From: WOODS, RICHARD [SMTP:wo...@sensormatic.com] > Sent: Tuesday, March 09, 1999 11:15 AM > To: emc-p...@majordomo.ieee.org; t...@world.std.com > Subject: RE: Rack System Safety (UL1950/EN 60950) Questions > > 1. Peter, equipment with the standard NEMA plug is considered to be > Class A.. > 2. Equipment using the heavy duty Industrial plugs complying with > IEC > are considered to be Class B. I have never seen those used inside rack > mounted equipment. > 3. If the power supply is UL "Listed", then temperature > measurements > are not required. However, most power supplies are categorized as > "Recognized" and are therefore incomplete in construction - that is, > they > cannot pass the safety requirements for a stand alone power supply. > Temperature measurements will be required. > 4. Stability is performed in a worst case situation, but reason is > also > taken into account. Most likely, you will determine that it is > possible and > reasonable to assume that more than one assembly can be extending at > the > same time. > 5. UL requires that all internal equipment be UL Listed or > Recognized. > > --- > From: pe...@itl.co.il [SMTP:pe...@itl.co.il] > Sent: Tuesday, March 09, 1999 11:26 AM > To: emc-p...@majordomo.ieee.org; t...@world.std.com > Subject: Rack System Safety (UL1950/EN 60950) Questions > > Dear All, > > I would like to know some of your professional advice on some > issues reagrding rack systems to be evaluated to UL1950/EN 60 > 950. > > 1. For the North America, does a NEMA 125 V, 20 A plug meet the > pluggable B definition? > > 2. What are some plug configurations which will meet the > pluggable B equipment requirements for North America and > Europe? > > 3. Does anyone have experience with UL and/or CSA and/or TUV > when testing a unit employing a Recognized/Certified/Approved > computer type "totally enclosed" power supply? I am interested > to > know if temperatures should be monitored within such a power > supply. So far, I have been asked to thermocouple various points > > within the power supply and as you all know, it could get very > crowded in there. I am interested to know if someone out there > knows if such a waiver exists for totally enclosed Approved > power > supplies. > > 4. When conducting stability tests for rack systems, should all > the > serviceable card cages be extended out or is it enough to do it > one > at a time. > > 5. For a CSA NRTLC unit employed in the rack system, does > anyone know if the CSA NRTLC Mark is automatically accepted by > UL or does UL require that the unit must be re-investigated and > placed under their Follow-Up Program? > > 6. Has the US Robotics Listed "Sporster" card modem been > evaluated to UL1950 Third Edition? > > 7. Can I List/Certify a rack system to UL1950 Third Edition if > the > units within it have been Listed/Certified to UL1950 First > and/or > Second Editions? I do not think so, but am interested to hear > your > opinions. > > 8. How is a CB test report done for a rack system which consists > > of previously Listed/Certified/Approved units? Does the CB > scheme > Recognize the Approvals of the various test agencies > (UL/CSA/TUV)? > > Thanks in advance. > > > PETER S. MERGUERIAN > MANAGING DIRECTOR > PRODUCT TESTING DIVISION > I.T.L. (PRODUCT TESTING) LTD. > HACHAROSHET 26, P.O.B. 211 > OR YEHUDA 60251, ISRAEL > > TEL: 972-3-5339022 > FAX: 972-3-5339019 > E-MAIL: pe...@itl.co.il > Visit our Website: http://www.itl.co.il > > --------- > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). > > --------- > This message is coming from the emc-pstc discussion list. > To cancel your subscription, send mail to majord...@ieee.org > with the single line: "unsubscribe emc-pstc" (without the > quotes). For help, send mail to ed.pr...@cubic.com, > j...@gwmail.monarch.com, ri...@sdd.hp.com, or > roger.volgst...@compaq.com (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators). --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to majord...@ieee.org with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to ed.pr...@cubic.com, j...@gwmail.monarch.com, ri...@sdd.hp.com, or roger.volgst...@compaq.com (the list administrators).