On Thursday 29 December 2016 19:01:33 Gene Heskett wrote: > On Thursday 29 December 2016 13:35:14 Jon Elson wrote: > > On 12/29/2016 11:19 AM, Gene Heskett wrote: > > > And there went the reversed hookup protection. :) > > > > No, the diodes are in the power SUPPLY, so the modular > > supply is running near the designed voltage, but the load > > gets a lower voltage. > > > > >> Jon > > > > > > How did you get that mod past the nuclear regulators? I'd had a > > > couple mods that genuinely improved the pix coming out of a tv > > > camera, rejected by lesser air force *crats who wouldn't know a > > > 1n34 diode from a 4 ton transformer. Pain in the a$$ they are. > > > They do not understand the technology at all, and do their damnest > > > to freeze the technology at the point the maker boxed it for > > > shipping. > > > > The national labs do have "electrical safety inspectors" who > > check everything that has a power cord. Since this unit > > plugs into a power and cooling frame, they generally don't > > even look at it. Mostly they ohm out the safety ground to > > frame resistance and make sure hot and neutral are isolated, > > and then they are happy and put an approved sticker on it. > > > > Jon > > Humm, VTA stuff. But at least we can get something before the next > 4th of July. > Darn it, I meant CTA, for Cover Their A$$ above.
> And, I am now a wee bit schmardter. When I wired that box, I brought > the line cord in and hooked it up to the 60 volt Z motor supply, then > continued the bus to the 42 volt supplies for the X motor, and then on > to this supply. Putting the filter on this supply helped, but only a > few percentage points less noise. So I grabbed a couple wire nuts and > bypassed the 60 volt supplies lines, including the static ground, and > the pair of supplies I intended to drive the x motor with, spent about > 3 hours stinking the place up about 3 weeks back, so they were removed > and I ordered another, whose last day to arrive was today, but I not > seen hide nor hair of it yet. > > So with the big supply out of the picture, it all seems to work. The > about 2 volts p-p at the ground terminal of the encoder cable was a > bit over 400mv, so I was able to add some code to scale the encoder to > the hal file. Looking at the velocity on the halscope, its about a 20% > of average with the waveform period matching one full cycle of the > quadrature. D I've been using a green highliter to mark up the stuff > for my averager in a printout of the mills hal file, which should > reduce that periodic noise to 25% of its cuttent value, while > injecting a phase delay of 2 edges gone by if it was being fed back to > a PID, which it isn't. So next thought is that the noise from the big > supply damaged both of the x motors supplies. > > So I am going to reroute the power wiring so it hits a terminal board > and the little supply hooked direct, first, and from that terminal, > feed the Z PSU thru this filter, and the X thru another filter I'll > cabbage from another computer psu since I have more dead ones. So all > three are sourced from the same terminal strip, but each of the bigger > supplies will have a noise board in its power leads. > > Thats the plan right now anyway. I went out an picked up a dead psu, > opened it up, but the line filters were laid out as an odd shaped > corner of its PCB, so I clamped onto the heat sink in the mills vice, > and used an old 1/8" mill to cut it out of the main PCB, driving it > slowly with the mills keyboard. Now I'll make a box out of dbl-sided > raw pcb to put both of them in tomorrow and fasten it to the outside > of the main box and run some wire to the little 5 volter, and extend > that back to a hot feed from a switch that will turn the pi and the > monitor off, then run another bit of SJ from the switched duplex that > will turn off all the higher powered stuff in addition to that 4 foot > high powered (4000 lumens) daylight led on the bracket about 34" above > the bed. And anything else plugged into the duplex above the spindle. > Then we'll see how much #@$% noise we have. > > Good thing I've got until I fall over to get this done. The bad part > is like concrete cracking, the question is not will it, but when, > because it will. :) > > Cheers, Gene Heskett 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> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, SlashDot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
