On Wednesday 03 February 2016 13:52:16 Dave Cole wrote: > I've seen some really wierd issues with some SSRs. I think that some > are not setup internally as they depict. > > Because of that I tend to avoid them when I can. However in some > applications they are the only way to go. > You might want to consider using relays for this application instead. > Drive the relays with the SSRs if you need to. > > Automation Direct has cheap 15 amp relays. Use two contacts in > parallel if you need more capacity and they will likely last a very > long time. > > Dave > Well, I appear to have it solved. When I did check, somehow the main SSR was being turned off quite quickly regardless of the delay I put in the timer. THe soft start was working as expected. I apparently wrote a buggy hal file.
But I hadn't named stuff quite right, and the code 535 lines down in the hal file was difficult to trace, so I renamed some stuff with more descriptive names, then went 530 lines down in the file and nuked everything in that section except the 5i25's gpio setup for pins 8 and 9 on J3, which of course are also 8 & 9 on the BoB. Then I reconstructed the charge pump chain and the time delays, checking those as I went along, but before I had rewired the box more in line with Jon's suggestion, I also ripped out my original pump detectors and installed two of the newer design with schottky diodes, which gave a little more gate drive for the hexfets that controlled the SSR's. Watching both the scope and the leds on the SSR's I made sure it was doing what I wanted with perhaps a bit more delay in the off because the gate voltage was about .8 volts higher with the schottky diodes doing the pumping. Then I did as Jon suggested and paralleled the hot terminals of the SSR's, then took what I now called *-hard signals SSR output to the end of the resistor, tested that, worked. Then connected the load side of the *soft SSR to hit the load end of the resistor, where the high side of all the toroids were also connected. So now the on sequence is turn on the *-hard, 1 second after I have enabled the machine which feeds the resistor, the other end of which feeds the toroids. This allows the caps to start charging up. 10 seconds later, when the caps are only 5 volts or so below fully charged, the soft timer finally goes true, enabling the pump signal to reach the second SSR and turn it on. That effectively ties both ends of the resistor together and feeds unrestricted power to the toroids. Then when I unclick either of the machine buttons, the *hard pump is stopped in about 3/4 second (software time is .1 secs, discharge time of the detector is nominally 1/2 sec) and the hard SSR is turned off, effectively switching the resistor back into the circuit. And about 3 secs later, the soft SSR is turned off, completely disconnecting the toroids and the bleeders will discharge the caps in another 10 minutes or so. I can likely speed that up to do it all in 1 second, but this way I can see the SSR'd leds confirming it if the lid is off that box. Now I have spent 20 minutes doing a slow dance on those 2 buttons, and haven't tripped the breaker yet, probably more than 50 full cycles. So I believe I have it whupped. Bout time, thats for sure. Now I can go back to slowly assembling mahogany pieces, and while glue is setting in clamps, I can work on a mount for the endoscope camera. But I haven't conjured up a design that will allow it to be quickly removed to get it out of the way of wandering clamp bolts and such, yet allow it to be remounted, still in the established calibration, when I need it. That is a lesson I learned from the smaller mill, I wiped the whole mount right off the side of the head casting with a tall clamp bolt. Perhaps I can borrow the design of a QC toolpost? But horizontally mounted, in miniature, on the bottom of the spindle lock ring. Still cogitating on that. I'll have to obtain a 45 degree dovetail cutter for that as I don't hardly have some more of that item on the tool rack I should build. :) 3pm, I think there is a cold pork chop calling itself breakfast in the fridge. 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=272487151&iu=/4140 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
