What about Al electrolytics? Like, for power supply bulk filtering? The furnace controller will be seeing 34 Vdc peak, does that mean 100v caps?
Yes, that's what I'd do. Also, with electrolytics, you need to pay attention to the temp rating. 85C rated caps are for cheap consumer junk. You want at least 105C for industrial equpt, IMO, and 125C is better if you don't mind the cost and increased board real estate. The lifetime of an electrolytic cap depends exponentially upon the difference (rated temp - operating temp), so using higher rated temps is a very good idea. Nichicon has a long app note talking about electrolytic cap lifetime issues. Google for it, it's worth reading. Also, a Google search will turn up lots of info about how to properly select an electrolytic cap. Stuart _______________________________________________ geda-user mailing list geda-user@moria.seul.org http://www.seul.org/cgi-bin/mailman/listinfo/geda-user