Hi Ted: Thanks for the bonding and grounding (Ingalls) report.
To me, attachment 12, current testing of the washers, was most meaningful. The report notes that (internal star washer) contact area is less than a traditional (shipbuilding) bond. Nevertheless, the resistance of the system (two coated bars separated by the washer) was 11 milliohms at 55 amps! And held steady for 5 minutes! The conclusion is star washers can be used in place of cleaning to bright metal! Wow! Rich -----Original Message----- From: Ted Eckert <[email protected]> Sent: Wednesday, August 8, 2018 11:26 AM To: [email protected] Subject: Re: [PSES] External toothed star washer used in earth connection These references are in relation to ship building, but may be of interest to anybody who wants to look at star tooth washer bonding in detail. http://www.public.navy.mil/navsafecen/Documents/afloat/Surface/Rsrcs/References/MIL-STD-1310H.PDF https://nsrp.org/wp-content/uploads/2015/10/Deliverable-2011-452-Improved_Bonding_Grounding_Final_Report-Ingalls_Shipbuilding.pdf The second link even includes a table showing the torque required to penetrate paint with various washers. (See table 2) Ted Eckert Microsoft Corporation - ---------------------------------------------------------------- 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]>
