I have a product being reviewed for compliance, a computer/display for use in outdoor environments, and UL/CSA/IEC 60950-22 was said to apply.
John Cochran STRONGARM Designs Ph: 215-443-3400 x219 From: Doug Powell [mailto:[email protected]] Sent: Thursday, November 20, 2014 12:51 PM To: [email protected] Subject: [PSES] UL 1740 - Wet Locations vs Outdoor All, I am in review of construction and testing requirements for a product suing UL 1740 - Robotics and Robotic Equipment. I am using this standard in conjunction with ANSI RIA R15.06. The device is not stationary; it is tethered and self-propelled. It is powered by a universal input of 90-254 VAC, 50-60 Hz and it does produce secondary voltages as high as ± 600 V DC. I hope someone here can clarify my concerns about the requirements for wet locations vs outdoor. I anticipate that this product could be used in any type of weather although this has not been discussed with the client. In UL 1740 the definition of a Wet Location is "Portions of an indoor installation where occasional or continuous exposure to water or other liquids is anticipated". UL 1740 has considerations such as reduced wet contact voltage limits and a brief mention of enclosure tests for spraying water, but no modification for safety spacings or any other concern. Outdoor use is only mentioned a few times, twice as footnotes in sheet metal minimum thickness tables and once in the section for outdoor-use tests where it refers to solely to requirements of UL 50. RIA R15.06 does mention specification of intended use & limits including outdoor in terms of risk assessment. I suppose it bugs me a little that there is so little attention paid to the possibility of water in the environment (I am aware of submersible robotic vehicles being approved to this standard, although this is not the case in this instance). Is it possible that the committee did not cover this matter in detail because they thought the Risk Assessment would take up the slack? The client is especially concerned about safety and has actually suggested multiple levels of redundancy with regard to isolation and insulation. My feeling is that I should at least apply some of the wet location provisions. Any insights or experiences that can be offered are much appreciated. Thank you, ~Doug -- Douglas E Powell [email protected]<mailto:[email protected]> 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 <[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 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)<http://www.ieee-pses.org/list.html> List rules: http://www.ieee-pses.org/listrules.html 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]>
