Re: Bad Fuse vs. Good Fuse
I have seen one instance where a fuse opened during a vibration test. I think that was a BAD FUSE. Best Regards Bob Schlentz This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
RE: Use of a triangle on warning labels
European Community Safety Signs Directive (EEC/92/58) Warning - black bordered triangle with yellow back ground and black symbol Prohibition - red circle and red diagonal line, white background, black symbol Mandatory - circle, blue background, white symbol Information - square, green background For UK refer to HS Safety signs and signals regs 1996. Regards, Chris ___ Chris James Engineering Services Manager Dolby Laboratories, Inc. (UK) Direct: 01793 842136 From: POWELL, DOUG [mailto:doug.pow...@aei.com] Sent: 13 May 2003 00:53 To: EMC-PSTC (E-mail) Subject: Use of a triangle on warning labels Hello group, It has become apparent to me that various standards require triangles at times when others do not. For example, IEC 61010-1 Table 1 only indicates 3 symbols that have the triangle enclosing the symbol. While, IEC 60417 does not indicate this. One that seems to be missing from IEC 61010-1 is the exclamation point in triangle. I've reviewed IEC 60204-1, EN50178, EN60950 as well and I find varying requirements, some more than others. SEMI S2 seems to indicate that nearly every symbol belongs in a triangle. I'm guessing that if it is an informational symbol, you do not use the triangle, but countering this, I have seen the hearing protection warning in a circle without the triangle. Does anyone know of a reliable rule-of-thumb for when to use a triangle on an IEC/ISO international warning symbol? By the way, here's a trivia question to which I do know the answer: On the circle-bar label warning, which angle does the slash take, from 10:00 to 4:00 or from 2:00 to 8:00 on the clock face? thanks, -doug Douglas E. Powell Regulatory Compliance Engineer Advanced Energy Industries, Inc. Fort Collins, CO 80535 USA ___ This message, including any attachments, may contain information that is confidential and proprietary information of Advanced Energy Industries, Inc. The dissemination, distribution, use or copying of this message or any of its attachments is strictly prohibited without the express written consent of Advanced Energy Industries, Inc. This message (including any attachments) may contain confidential information intended for a specific individual and purpose. If you are not the intended recipient, delete this message. If you are not the intended recipient, disclosing, copying, distributing, or taking any action based on this message is strictly prohibited.
Re: Use of Voltage Probe
I read in !emc-pstc that ITL-EMC User Group itl-...@itl.co.il wrote (in 2D1037012914D4118DB8204C4F4F5020275AD1@ITLLTD01) about 'Use of Voltage Probe' on Sun, 25 May 2003: According to Section 4.1.3 Voltage probes of ANSI C63.4, A voltage probe may be used for radio-noise voltage measurements when measurements are made at a user's installation (see 5.6) or when the ac current level exceeds the current-carrying capability of commercially available LISNs. For such measurements, the method shown on Figure 4 may be used. Special precautions shall be taken to establish a reference ground for the measurements. This is an example of useless wording in a standard. What 'special precautions' did the authors have in mind? To achieve or avoid what? They don't tell us, and coyness is definitely not a virtue in such a case. All it does is create confusion, as we see here. Accord to Section 5.6 Testing at manufacturer's location or user's installation, The voltage probe (see 4.1.3) shall be used for ac powerline conducted emission measurements. (See IEEE Std 13-1988 for additional information.) Neither a reference groundplane nor an LISN shall be installed for user's installation testing unless one or both are to be a permanent part of the installation. The above sections seem to me to contradict one another regarding the reference groundplane. No, because you have no 'grounds' (ouch!) for assuming that the 'special precautions' imply 'use a ground plane'. Can we interpret the above (Section 4.1.3 Special precautions shall be taken to establish a reference ground for the measurements.) to be applicable only when testing in the laboratory and the ac current level exceeds the current-carrying capability of commercially available LISNs? Please comment. No, it is reasonable and technically correct to pay attention to where you ground the voltmeter connected to the probe, wherever the measurements are carried out. It would be logical to connect it to the enclosure of the EUT, if it is metal, with the shortest practicable lead. -- Regards, John Woodgate, OOO - Own Opinions Only. http://www.jmwa.demon.co.uk Interested in professional sound reinforcement and distribution? Then go to http://www.isce.org.uk PLEASE do NOT copy news posts to me by E-MAIL! This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
Use of Voltage Probe
Dear all, According to Section 4.1.3 Voltage probes of ANSI C63.4, A voltage probe may be used for radio-noise voltage measurements when measurements are made at a user's installation (see 5.6) or when the ac current level exceeds the current-carrying capability of commercially available LISNs. For such measurements, the method shown on Figure 4 may be used. Special precautions shall be taken to establish a reference ground for the measurements. Accord to Section 5.6 Testing at manufacturer's location or user's installation, The voltage probe (see 4.1.3) shall be used for ac powerline conducted emission measurements. (See IEEE Std 13-1988 for additional information.) Neither a reference groundplane nor an LISN shall be installed for user's installation testing unless one or both are to be a permanent part of the installation. The above sections seem to me to contradict one another regarding the reference groundplane. Can we interpret the above (Section 4.1.3 Special precautions shall be taken to establish a reference ground for the measurements.) to be applicable only when testing in the laboratory and the ac current level exceeds the current-carrying capability of commercially available LISNs? Please comment. Thank you in advance David Shidlowsky Technical Writer EMC Laboratory ITL (Product Testing) Ltd. Kfar Bin Nun Israel Tel: +972-8-9797799 Fax: +972-8-9797702 Email: dav...@itl.co.il http://www.itl.co.il http://www.i-spec.com This e-mail message may contain privileged or confidential information. If you are not the intended recipient, you may not disclose, use, disseminate, distribute, copy or rely upon this message or attachment in any way. If you received this e-mail message in error, please return by forwarding the message and its attachments to the sender. This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: majord...@ieee.org with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Dave Heald: emc_p...@symbol.com For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org Archive is being moved, we will announce when it is back on-line. All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
