The 'star' washer should be gas-tight seal. If a serrated-headed screw is even less of seal, than higher risk-level indicated. Faulty logic? Anyone else observe failure modes of ground-bond hardware?
The CSA Design Manuals (not all standards have a respective D.M.) have drawings and specifications for acceptable materials and combinations of ground bond hardware. Recommended. Brian -----Original Message----- From: John Woodgate [mailto:[email protected]] Sent: Monday, March 02, 2015 11:47 AM To: [email protected] Subject: Re: [PSES] Serrated head screws for grounding/bonding In message <blupr02mb1160acb7f7c87a911caabc6c1...@blupr02mb116.namprd02.prod.outlook .com>, dated Mon, 2 Mar 2015, Brian Oconnell <[email protected]> writes: >Saw exactly this happen on flight deck of USS Midway during 1979. While >troubleshooting APD10 radar, the hydraulics guy that was helping me >shorted the 400Hz bus to the box containing the power supply, and a >star washer vaporized because part of the converter was floated. The >star washer was not authorized construction. I was talking about serrated-headed screws, not star washers. - ---------------------------------------------------------------- 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.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://www.ieee-pses.org/list.html (including how to unsubscribe) 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]>
