This is a question for the safety testing engineers. We have products that contain 12V/24V DC cooling fans that cool either the PSU or processing circuits. The fan speeds are reduced with basically a series resistor to reduce audio noise. The safety testing agency demands to know the exact model number and CFM of each fan even though the products continue to function during the stalled rotor test. Obviously there is temperature rise within the product. My question is why does the agency list the exact model number and CFM rating of the fan even though it doesn't run at full speed and the product continues to function with a stalled rotor. We have to use alternative fans due to supply issues and this incurs considerable test agency costs as the agency won't accept a manufacturers range of fans without testing each one. All fans used are UL listed and the products are tested to IEC/UL 60065.
Your comments would be appreciated. Many thanks in advance. Ian McBurney Design & Compliance Engineer. Allen & Heath Ltd. Kernick Industrial Estate, Penryn, Cornwall. TR10 9LU. UK T: 01326 372070 E: [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]>
