On Tuesday 02 February 2016 21:46:34 Jon Elson wrote: > On 02/02/2016 06:14 PM, Gene Heskett wrote: > > It basically consists of two SSR's in series, the first one being > > the main switch that enables AC power to reach the transformer by > > way of a 51 Ohm 200 watt inrush limiting resistor. And that after > > the filters are charged, nominally 10 seconds, a second SSR is > > fired to short that resistor, allowing the supply to make full > > output. Controlled by a couple timers driven by the > > motion.machine_is_on signal. > > Hmmm, maybe this is the problem. Maybe, due to the way the > zero-crossing circuits work, putting two SSRs in series > totally fouls up the internal logic. it seems you could put > the two relays in parallel, one with the resistor in series > with that relay. So, you turn on the relays exactly as > before. the one with the series resistor first, then the > one with no resistor. My GUESS, and it IS a guess, is that > somehow, with the two relays in series, and that they have > zero voltage switching logic in them, that they fool each > other and end up passing only half-wave power to the > transformer. Does the transformer clunk right when this > breaker-tripping event occurs?
I don't hear it, but since they are toroids on ferrite cores, would I hear that? They are very quiet otherwise. > If the transformer is fed > half-wave power, the core will saturate in barely more than > one line cycle, and a tripped breaker seems quite likely. > Zero-crossing SSRs are really NOT good for transformers, > anyway, as they just about guarantee a saturated start for > the transformer, anyway. What you REALLY want is a relay > that always closes on the voltage peak, but they don't make > those. Noted previously. And it hurts. I think that may be some fraction of the why I had to put a 30 amp breaker on that circuit in the first place. Bears investigating for sure, thanks Jon. > Anyway, it seems my idea would require only moving a couple > wires, so you might try it. > > Jon > I think that is what I have, but possibly not, Jon. It wouldn't be at all hard to fix in the event its not that way. But again, it runs all day, then trips the breaker coincident with ther button click, seconds BEFORE either SSR is turned off. Thats what doesn't grok. Weirdsville. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=267308311&iu=/4140 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
