I use CADDOCK Model MG725 resistors installed in a small plastic tube in my Lab. Don't forget that the wire between the resistors has to have a high voltage rating as well. -David G
-----Original Message----- From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: Thursday, March 07, 2013 1:43 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] test setup for table top ungrounded equipment 61000-4-2 IEC:2008 figure 6 page 20 In message <64D32EE8B9CBDD44963ACB076A5F6ABB0263F54F@Mailbox-Tech.lecotech.local>, dated Thu, 7 Mar 2013, "Kunde, Brian" <brian_ku...@lecotc.com> writes: >Do you make your own bleed-off cables (with two 470K? resistors). If >so, what kind of resistors do you use? I’ve seen different labs use >different types of resistors which I think can make a big difference. Indeed, but there need be no anxiety; metal-glaze resistors rated for operation at kilovolts are available and not costly. For example: http://www.vishay.com/ppg?28733 >One lab I was at used surface mount resistors mounted on a small PC >card >which was encapsulated in potting compound. Though it seemed like >a good >idea I have my doubts. So do I; I doubt the potting compound is rated for many kV/mm! >I've heard metal film or thin film resistors can arc or track over the >>surface. Those rated at 100 V, 250 V or 500 V certainly can. >One lab I was at used huge wire wound resistors but they can arc >between >the windings at high voltages. I've been told that carbon >composition >resistors are the best and get the larger wattages such as >1 watt or larger. We use 2 watt Carbon resistors which work well at >8kv. But they notoriously go high in value when repeatedly subjected to high voltages. And you might not know that had happened. -- OOO - Own Opinions Only. See www.jmwa.demon.co.uk SHOCK HORROR! Dinosaur-like DNA found in chicken and turkey meals John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com> - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. To post a message to the list, send your e-mail to <emc-p...@ieee.org> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/ can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/ Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas <emcp...@radiusnorth.net> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
