Hello Chris, Some reviewers might reject the construction without a lock washer for a different reason. A split or star-tooth lock washer will cut through paint, oxidation, or coatings on a surface giving additional bonding contact. I've had reviewers who didn't trust the bonding connection through the threads of the nut and stud and insisted of a backup through the mating surface of the base of the nut. Please note that I'm not saying that this is the correct interpretation. It's only one that I've run into.
I can also imagine objections due to the force needed to put a nyloc nut on in the first place. An inexperienced person might not fully tighten the nut as it will provide more resistance to tightening as it is screwed further onto the stud. I can see it being easier to have the nut not fully tightened as a result. Again, I'm not stating that these are reasons the construction will get rejected. They are just possible objections of a reviewer. Ted Eckert The opinions expressed are my own and do not necessarily reflect those of my employer. From: Chris Wordley <[email protected]> Sent: Monday, November 15, 2021 6:06 AM To: [email protected] Subject: [EXTERNAL] [PSES] Nyloc Nuts Hello We sometimes come across products that employ a Nyloc nut as the sole means of securing (preventing accidental loosening of) a protective earth connection on a threaded stud. I've heard various views on the acceptability of this type of construction - some consider it OK provided the temperature is not high enough to cause the nylon insert to soften, others think that a separate spring/serrated washer is required since the nylon cannot be depended on in the longer term. I'd be interested to hear the views of others, particularly any CB or similar labs. I failed to uncover any IECEE decisions on this subject. Best Regards Chris - ---------------------------------------------------------------- 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]<mailto:[email protected]>> All emc-pstc postings are archived and searchable on the web at: http://www.ieee-pses.org/emc-pstc.html<https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2Femc-pstc.html&data=04%7C01%7Cted.eckert%40microsoft.com%7C98ad442c5d754f6f451008d9a8412546%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C637725820049298897%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=qtfgbDc4iLTAts7I2rn5GohRBzU2OYmQF1jQtrcw0AI%3D&reserved=0> Attachments are not permitted but the IEEE PSES Online Communities site at http://product-compliance.oc.ieee.org/<https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fproduct-compliance.oc.ieee.org%2F&data=04%7C01%7Cted.eckert%40microsoft.com%7C98ad442c5d754f6f451008d9a8412546%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C637725820049308894%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=U8uYCzJxKZ4U%2FLiYxG%2FGASnhcEsAmvSDDiGuoePyzy8%3D&reserved=0> can be used for graphics (in well-used formats), large files, etc. Website: http://www.ieee-pses.org/<https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2F&data=04%7C01%7Cted.eckert%40microsoft.com%7C98ad442c5d754f6f451008d9a8412546%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C637725820049308894%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=Xm%2FV%2F7G2X%2FVrMqfaNJnD1ePgHY0dtYQnvsssgjg8Sng%3D&reserved=0> Instructions: http://www.ieee-pses.org/list.html (including how to unsubscribe)<https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2Flist.html&data=04%7C01%7Cted.eckert%40microsoft.com%7C98ad442c5d754f6f451008d9a8412546%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C637725820049318879%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=9fJf1nAm2809LefYGCZ6sUM4ahRHpsRrkPxla8EdIhI%3D&reserved=0> List rules: http://www.ieee-pses.org/listrules.html<https://nam06.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.ieee-pses.org%2Flistrules.html&data=04%7C01%7Cted.eckert%40microsoft.com%7C98ad442c5d754f6f451008d9a8412546%7C72f988bf86f141af91ab2d7cd011db47%7C0%7C0%7C637725820049318879%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000&sdata=LP0r3SSIS9Frm3aV21J39wb0dSbrenMyPP5zGKbprhA%3D&reserved=0> For help, send mail to the list administrators: Scott Douglas <[email protected]<mailto:[email protected]>> Mike Cantwell <[email protected]<mailto:[email protected]>> For policy questions, send mail to: Jim Bacher <[email protected]<mailto:[email protected]>> David Heald <[email protected]<mailto:[email protected]>> - ---------------------------------------------------------------- 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]>
