This thread has missed one major standard: UL991 “Standard for Tests for Safety-Related Controls Employing Solid-State Devices”, which in the scenario presented would be needed ALONG WITH UL1998 for the software, and the right approvals on whatever electro-mechanical device ultimately opens or closes a circuit. The UL991 requirements are a mix of EMC immunity and environmental withstand, with FMEA used to determine what components/subsystems require testing.
Jim Eichner, P.Eng. Compliance Engineering Manager Xantrex Technology Inc. phone: (604) 422-2546 fax: (604) 420-1591 e-mail: [email protected] web: <http://www.xantrex.com> www.xantrex.com Confidentiality Notice: This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. From: [email protected] [mailto:[email protected]] On Behalf Of Doug Nix Sent: Friday, July 20, 2007 10:42 AM To: [email protected] Subject: Re: Interlock Circuits Firmware/Silicon Controlled One more interesting little point - In the ANSI/RIA 15.06 Robot standard and the CSA Z434 Robot standard, programmable controllers are allowed in the safety related parts of the control system as long as they are NRTL approved, or in Canada, approved by an SCC accredited body. There are NO NRTL's and NO SCC accredited bodies that will certify such a controller at this time. In my practice we have allowed EU approved controllers for this purpose, since they have been reviewed an approved by accredited organizations under standards which are close adaptations of ISO and IEC standards. In my opinion, unless you plan to build a significant quantity of the product it's probably unwise to try to 'roll your own' software based safety controller. Hardware is well proven and well accepted for good reason. -- Doug Nix, A.Sc.T. IEEE PSES Kitchener-Waterloo Section, Ontario, Canada [email protected] mobile (519) 729-5704 fax (519) 653-1318 Find me LinkedIn at http://www.linkedin.com/in/dougnix - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html 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] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
