My client, manufactures UL Listed and European Approved ITE equipment. For products with appliance inlet, earthing means is accomplished by terminating a green/yellow lead to the appliance inlet terminal; other end is terminated by a crimp-type closed loop connector and terminated to a stud or screw by a nut and washer. This stud or screw on chassis is called the protective earthing terminal and the IEC417 5019a earthing symbol is marked adjacent to it.
My client exhibited today two products from two different reputable ITE manufacturers (let's keep 'em nameless). Both products were US/Canada Listed and GS Approved. Both products had metal enclosures and employed 3-pin (ie earthed) appliance inlets with NO earthing lead from the appliance inlet earthing terminal to chassis; earthing was accomplished by the appliance inlet body in contact with the chassis.
Question 1: Can we rely on the two screws securing the appliance inlet as a means for bonding? Over the years, I have been told by various safety agencies that such construction is unacceptable.
Question 2: Am I correct in assuming that the appliance earthing terminal for the above Listed/Certified products was considered as the main protective earthing terminal?
Question 3: Why do most other ITE manufacturers use the "stud on the chassis method" for protective earthing terminal?
Looking forward to hearing your comments from you all over the world!
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).
