On Monday 14 December 2015 20:51:46 andy pugh wrote: > > As I reported, I have 4 of them coming. > > The forcibly guided relay for mine arrived today, so I finished > assembling the PSU and then drew a schematic of what I ended up with. > > I am using the physical relay to ensure that I can't possibly power > the system up with the discharge resistor in circuit. So, if the > discharge contacts on the relay weld closed, the input SSR can't be > energised. > I ended up with a 6-pole relay. A 2-pole NO/NC relay would have > worked, though. > > 620R is actually a bit high for the soft-start resistor. It seems > about right for the discharge resistor.
I'll use that 51x200 watter, basically because thats what I have. I may give some thought toward using another to bring in a bleeder, but that would have to be on the DC side independent of the AC. The concern there would be making sure it shuts off once triggered. I'd have to give some thought to ways to assure that, such that it could not be restarted until it was off. Or just use two 7 watt night lights in which case I'd have a pilot light of sorts, which would also be a seriously slow bleeder. Just one looked ok, but did not survive very many motor dirction reversals due to the voltage spike on the caps that created. 2 in series should last till the rapture... I've such a setup on the x10 circuit that runs my evening front deck lights, been there since 2008. No lamp failures. ==================================== I should probably take this opportunity to clarify my polishing of the E-Core laminations in that contactor, which silenced it. As I'm aware of why its laminated in the first place, the motions against the sandpaper were always along the length of the stack, never across it so as not to smear the metal of one lamination over to an adjacent one, thereby creating an eddy current short. That would raise the losses and create heating in the E-Core. From the almost vanishing temp rise I observed in the hour it took to make and eat our dinner, I believe I was successfull, as the core rise was about what one would expect would radiate inward from the coil form itself. IOW, the dark line of varnish between the laminations should never be bridged for any reason. Taking a file to do that would almost certainly be a no-no for that reason. 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) Some mill pix are at: Genes Web page <http://geneslinuxbox.net:6309/gene/GO704-pix> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
