1. NFPA 70 2. the standard-specific Design Manual published by CSA.
3. C22.2 No. 0.4-04, clause 4.4.5 Conductive elements whose surfaces are coated with a poorly conducting material such as paint, and between which electrical contact is essential to a bond, shall have their coatings removed at the point of contact unless an investigation of the onstruction and manufacturing process demonstrates that the requirements for impedance and fault capacity can be met without removing the surface coating. 4. C22.2 No. 0.4-04, clause 3.4.4.11 Contact between surfaces, one or both of which are unplated ferrous metal, shall not be considered sufficiently reliable for electrical bonding purposes except in the compression zone of a suitable conductive fastener (e.g., screw, bolt, or nut) where the compression of the metal parts or the cutting action of the fastener parts is such that oxidation or corrosion is unlikely to reduce conductivity between the metal parts. 5. Various UL PAGs - focus on 508 and 60950 From: [email protected] [mailto:[email protected]]On Behalf Of [email protected] Sent: Tuesday, June 09, 2009 10:20 AM To: [email protected] Subject: lock washer in ground conduction path. There seem to be arguments for using a lock washer, particularly a star washer, between a ring lug and a chassis connection point since it could improve (lessen) the impedance of the circuit by breaking through surface oxides and corrosion. There are arguments against using lock washers in this manner, because they often have a smaller conductive cross-section than the ring lug itself and are not otherwise rated for electrical service. Does anyone know of any electrical design standard or authoritative guidance document that squarely addresses this question? Of course, for the issue of mechanical stability, a washer can be placed on the top side of the lug, and so not participate directly in the conduction path. Lauren Crane Product Regulatory Analyst Corporate Product EHS Lead Applied Materials Inc. Austin, TX 512 272-6540 [#922 26540] - 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 <[email protected]> All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc Graphics (in well-used formats), large files, etc. can be posted to that URL. 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 <[email protected]> Mike Cantwell <[email protected]> For policy questions, send mail to: Jim Bacher: <[email protected]> David Heald: <[email protected]>
