Is 'QVGS2' a new CCN? Brian
From: John Allen [mailto:jral...@productsafetyinc.com] Sent: Thursday, November 30, 2017 8:51 AM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Pickle Hi, To pass along the learning that came out of this............. A fuse did not have a tight enough tolerance, but we found a UL R/C Protector - QVG2S - that will open before the hazard. The NRTL agreed as long as we prove it opens before the hazard, UL 991 and 1998 are not required. Thanks again for the input and help, John ________________________________________ From: John Allen <jral...@productsafetyinc.com> Sent: Tuesday, November 28, 2017 3:02 PM To: EMC-PSTC@LISTSERV.IEEE.ORG Subject: Re: [PSES] Pickle Thanks everyone! Either test or re-design is required. I appreciate the input. John ________________________________________ From: Doug Powell <doug...@gmail.com> Sent: Tuesday, November 28, 2017 2:07 PM To: John Allen Cc: EMC-PSTC Subject: Re: [PSES] Pickle John, UL 991 is a test method for qualifying solid-state circuits for safety function. It is generally referenced by another standard and is not used as a primary certification standard as such. Additionally, semiconductors are not certified individually to UL 991 as this is not a component standard. It is very important that the circuits where the semiconductors are used be evaluated. If you are familiar with the EMC immunity testing of IEC/CISPR standards, it is very much like this. Radiated immunity, EFT, surge, ESD, etc. -Doug Douglas E Powell Laporte, Colorado USA http://www.linkedin.com/in/dougp01 Doug Powell | Professional Profile | LinkedIn www.linkedin.com View Doug Powell's professional profile on LinkedIn. LinkedIn is the world's largest business network, helping professionals like Doug Powell discover inside connections to recommended job candidates, industry experts, and business partners. On Tue, Nov 28, 2017 at 11:44 AM, John Allen <jral...@productsafetyinc.com> wrote: Hi, We have a pickle of a situation and wondering if anyone knows a simple fix......... We have a moving wall that complies with the maximum force limits of UL962. An IC measures the voltage of a resistor and if appropriate, allows the correct current to be sent to a motor that moves the wall. If too much current is allowed to the motor, the force created is greater than the limit. We have a fuse, but it won't open before the force is created. A UL991 investigation on the IC and Resistor circuit is necessary. I agree with that. That said - 1. I could not find any UL Recognized Component circuits that comply with UL 991. Is there such a category?? I searched UL's database for anything UL 991 and came up with a few categories. FSPC2 is a likely candidate, but the few Listings that are in there are heavy duty motor controllers or position sensing devices, etc. 2. If we redesign to not use the IC, won't we still be subjected to UL 991? If we use discrete components (resistors and capacitors vs ICs) does that get us out of UL 991? Any insight would be appreciated. Best Regards, John - ---------------------------------------------------------------- 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> Douglas E Powell doug...@gmail.com http://www.linkedin.com/in/dougp01 - ---------------------------------------------------------------- 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>
