On Tuesday 02 February 2016 21:55:10 Jon Elson wrote: > Gene, > > One detail. Is the breaker only tripping when you turn OFF > the SSR?
No Jon, I stretched the off delays, and the breaker is falling as soon as I click the off button. Thats 3 to 5 seconds BEFORE either SSR is turned off. And that puts the puzzle in a brand new category. I could easily believe the surge failure IF the breaker was falling coincident with turning off the SSR. But this doesn't calculate at all. > If so, this actually makes a lot of sense. Some > SSRs have a self-protective function that turns the SSR on > for a half-cycle if an overvoltage is experienced. (This is > usually an avalanche section built into the SCR or Triac > component.) If this gets triggered on shutoff of the > transformer due to leakage inductance in the primary > winding, it could get stuck in this mode until the breaker > pops. You might be able to fix it by putting a big snubber > across the SSR. Since the direct-feed SSR has a beefy > resistor across it, it seems like it might be the SSR that > is turned on first that would be susceptible to this mode. > But, you might try it on both - or put it spanning BOTH > SSRs. Something like .01 uF and 10 Ohms in series might be > where to start. > My hell-box doesn't have either of those in suitable voltage ratings. I do have some 8 ohm 20 watters, probably inductive as they were sold as audio dummy loads by the Shack when we had one. The caps would probably need to be kilovolt rated I'd imagine. I'l check, and rewire if needed tomorrow on the other suggestion. I did have it timed so the one across the resistor was turned off first, leaving power on thru the resistor until that one shut down 1 second later, giving a "soft shutdown" as it were. Thanks for the ideas Jon. Appreciated. 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
