Michael - If the filter is UL Recognized, you might wind up asking for trouble. First off, the markings on the outside of the can are what identify the filter as Recognized (mfg's. name and cat. no., and the backwards UR ligature). Removing the can removes traceability of the filter and that will cause FUS problems, on top of the type evaluation problems you'll have.
Next, the device is accepted by UL in a piece of ITE, based on the requirements for the filter itself. I don't have a copy of UL 1285 (if that's the correct number for appliance filters), but the clearances and creepages probably are different. Once you remove the can, you may wind up having to have the full requirements of UL 1950 applied to your filter, and that might be undesirable. If that filter already complies with IEC 950 or its derivatives, then there may be no safety issue. If the can changed the pollution degree (microenvironment, whatever), the clearances and creepages that apply might have changed. Reevaluating this will add time and money to your safety agency evaluations. You pays your money and you takes your chances. Regards, Peter L. Tarver Northern Telecom [email protected] ------------------------------ From: Michael Roy Hi everyone. I have a question about safety. I have a chassis with a standard IEC type input filter and simple on/off switch that goes to an enclosed switching power supply subassembly. As it is designed right now, all of the AC componants are enclosed in a metal box that mounts to the inside of the chassis. The connections are all 1/4 inch faston type crimps and are completely insulated. The main chassis itself will not be opened by the end user for any reason. My question: Can I do away with the steel around the input filter and on/off switch ? [email protected]
