Hello Group! 1. Per UL1950/EN60950 can any capacitor be used to bridge basic insulation between a TNV-3 circuit and a SELV circuit or should it be a Recognized/Certified Y-capacitor?
2. Can the insulation over an electrolytic capacitor be considered as insulation when evaluating spacings? One North American test lab refused to consider the insulation over the capacitor since "there is no control (traceability) over the material used to insulate the capacitor". However, after showing them competitors' products with their own test mark applied and where the plastic covering over electrolytic capacitors was used to provide basic insulation between the metal can and the earthed heat sink, the test lab accepted our customer's construction. What is the group's opinion? 3. Many times when we have tested power supplies for abnormals, electrolytic capacitors vented and emitted smoke. Under these conditions, our test lab usually is covered up with heavy smoke (reminds me of the fog in the Bay Area!) and the lab technicians are wearing "gas masks" (reminds me of the Gulf War!). We then applied the compliance criteria for the Abnormal Tests including Dielectric and Leakage Current Tests and found the power supplies fully compliant. What does the group think about smoke being emitted from equipment during Abnormal Testing? Should there be a standard requirement to measure the toxicity of the fumes? 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: [email protected] 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 [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
