Hi Mike. You wrote:
> Where do you put the AC mains fuse relative to the "X" capacitor used for the > EMI filter? > > How does the "accross the line" safety rating of the capacitor affect this > answer? > > Specifically. Would you put an X cap in the unfused area of the AC inlet > like the EMC fellow wants? What about a "Y" cap? X caps and Y caps are designed to be very high reliability components, self healing etc. and in the case of X1 caps, good for 4kV peaks. Filters that use these things generally need to be mounted right at the point where the mains supply enters the equipment, this invariably means before the fuse. The caps are designed to be as reliable as the wire that feeds them, and so can safely be put before the fuse without affecting the safety integrity of the equipment. I use these caps in filters that are permanently live from day one, before the fuse, but in the happy knowlege that there is a fuse up line somewhere rated to protect my mains supply cable. That's me anyway. Chris Dupres EMC Specialist. VG Microtech. [email protected] tel +44 (0) 1825 761077 fax +44 (0) 1825 768343 'Opinions expressed are personal, not necessarily Corporate'
