Hello Peter:
> 1. For the North America, does a NEMA 125 V, 20 A plug meet the > pluggable B definition? No. The objective of the Pluggable Type B connection is that of a reliable, non-defeatable earth connection. The NEMA 20 A plug uses the same earthing connection as the NEMA 15 A plug. The 15 A plug is notorious for having the earthing connection destroyed or removed in use. > 2. What are some plug configurations which will meet the > pluggable B equipment requirements for North America and > Europe? I'm afraid I can't answer this question. I suggest you ask UL or CSA. > 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. Any component, including component power supplies, must be tested for temperature rise in the end-product configuration. It is not necessary to measure all of the same points as was done for the power supply safety qualification. I choose a sub-set of those, especially the highest temperatures. If the highest temperatures are okay in the end-product, then it is a good assumption that the lower temperatures are also okay. I would expect that you would only need to test 20% of the total test points. > 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. Testing is almost always the worst-case condition, regardless whether such condition is not expected in normal service. "Doors, drawers, etc., which may be moved for servicing by the operator or by service personnel are placed in their most infavourable position, consistent with the manufacturer's instructions." > 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? The CSA NRTL mark means the unit is acceptable for use in any USA workplace. The unit need not be also certified by UL. If CSA certifies the unit to the bi-national standard, then the certification is accepted by UL if you should submit the unit to UL as part of another equipment. Otherwise, it does not make much sense to also submit the unit to UL. Both CSA and UL and all other NRTLs have follow-up programs. This is a NRTL requirement. > 6. Has the US Robotics Listed "Sporster" card modem been > evaluated to UL1950 Third Edition? If so, such certification would be marked on the unit or on the packaging accompanying the unit. In addition, it would appear in the UL Listed Products book. > 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. No. All certifications of components and sub-systems must be to the same or newer edition of the standard as for the entire equipment. (In most cases, certification to newer editions also means compliance to former editions.) By the way, the differences between editions rarely mean the hardware does not comply with newer requirements. Re-evaluating the hardware to the newer editions rarely results in a need to change the hardware. Its an exercise which costs the submittor money, and benefits the certifier, but has no effect on the safety of the equipment, and has no benefit to the customer. I have several products certified to IEC 60950 Amd 1, 2, and 3. We're adding some new models to these families. All new models must now be evaluated to Amds 1, 2, 3, and 4. No hardware changes, but I must go through a complete new evaluation because Amd 4 is now in effect. Since safety is realized in the hardware, and since there is no hardware change, what is the value of Amd 4? > 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)? A CB for a rack system must include CBs for each of the individual parts of the system. Or, each individual part must be evaluated in accordance with the standard. The NCB can use the listing/certification/ approval reports from other NCBs to reduce the amount of evaluation of those parts. But, the CB Report it issues must cover everything in the rack, either directly included in the CB Report or included as attachment CB Reports. Best regards, Rich ------------------------------------------------------------- Richard Nute Product Safety Engineer Hewlett-Packard Company Product Regulations Group AiO Division Tel : +1 619 655 3329 16399 West Bernardo Drive FAX : +1 619 655 4979 San Diego, California 92127 e-mail: ri...@sdd.hp.com ------------------------------------------------------------- --------- 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).
