RussellMc writes: > Be absolutely certain that the contacts are rated to handle the maximum A= C > voltage that will be encountered. >=20 > The AC load spec is almost always far more stringent than the DC load spe= c > and failure to note this can cause relay failure at well below apparent > rated (DC) value. >=20 >=20 >=20 > Russell Now, I am curious. Why would the AC load spec be more stringent? It would seem to me that DC conditions would be worse since the flow of current is always at it's peak unless one is closing the contacts on an inductive load at which point it would be less current while the field was building in the inductor. When the contacts opened, there could be a nasty arc if the inductor had built up enough magnetic field. In AC, you sort of roll the dice and the contacts could sometimes open or close right at a 0 crossing and nothing much would happen as far as sparks or spikes. The peak voltage, assuming a sine wave, would be roughly 1.4 times the RMS voltage. What am I missing? Martin McCormick WB5AGZ --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .