> here are some rough > calculations. I'm making this up as I'm typing. I remember something about > 7A steady state. Let's say the initial current is 70A at full voltage. > > I have been taught, and have used 7:1 as an inrush current ratio for > tungsten for the past 20 years without any problems. > ... Chris, please do whomever you are replying to and the rest of the list the courtesy of differntiating your responses from the original post. I use "> " at the start of each line to denote the original post, as most people do, but anything that makes it obvious is sufficient. I particularly object to you reproducing my signature line in your post as if I had written the whole thing. (Of course that should have been trimmed altogether, but that's probably too much to ask at this stage). ******************************************************************** Olin Lathrop, embedded systems consultant in Littleton Massachusetts (978) 742-9014, olin@embedinc.com, http://www.embedinc.com -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.