Hello James:
As for resistance of the connection, I doubt that there is significant difference. I have tested both with a high-current-sourcing milliohmeter. You can repeat the test and see if there is a difference in the resistance. (Even a loose connection will still pass the high current test.) A star washer is more likely to penetrate paint. However, a stud mounted in a panel is independent of paint. So, a lockwasher simply locks the nut to the stud and has little to no effect on the resistance of the connection. Best regards, Rich From: James Pawson (U3C) <ja...@unit3compliance.co.uk> Sent: Tuesday, February 15, 2022 7:34 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: [PSES] Earthing -- Star vs Spring/Split Washers Hello all, I've given myself a regular internet headache trying to understand the relative merits of spring vs star washers for use on an earth stud for protective earthing purposes. What is the conventional wisdom and justification? I know I can trust you folks to be above a simple "we've always done it this way" Can anyone point me towards any citable references or standards covering this subject? I promise I will write a blog post to pull the information together for future confused generations. Thanks and all the best, James James Pawson The EMC Problem Solver Unit 3 Compliance Ltd EMC : Environmental & Vibration : Electrical Safety : CE & UKCA : Consultancy <http://www.unit3compliance.co.uk/> www.unit3compliance.co.uk | <mailto:ja...@unit3compliance.co.uk> ja...@unit3compliance.co.uk +44(0)1274 911747 | +44(0)7811 139957 2 Wellington Business Park, New Lane, Bradford, BD4 8AL Registered in England and Wales # 10574298 - ---------------------------------------------------------------- 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://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 <sdoug...@ieee.org> Mike Cantwell <mcantw...@ieee.org> For policy questions, send mail to: Jim Bacher: <j.bac...@ieee.org> David Heald: <dhe...@gmail.com>
