Greetings Peter; Someone made the remark a while back that it was indeed possible to look at the output of a function, in this case the first pwmgen of a 5i25 with the prob-rfx2 firmware in it.
I've had a blowup, the ultimate cause of which I have not found yet, but from the damages done to the cnc4pc C1G BoB that I have found so far, I am inclined to think the spindle motor psu, or possibly something line powered failed. The C1G damages so far found are 1 blown 74ACT245N, and an almost invisible use of a ground trace on the pcb as a fuse. All the opto's in my spindle encoder would appear to have failed. Those I have a bag of, but that pcb makes the tinfoil of a pack of smokes look like boiler plate, so I'll have something I won't call fun replaceing them. I can run the x/z motors just fine, but the limit switches would appear to be closed as those leds are at full britness when its several inches from the switches. What happened is that I had started a short program that called for a 400 rpm spindle but had neglected to engage the headstocks back gear, so the motor took off and wound out to max speed before I could hit the big red button. And about 1/2 second before my hand hit the button, there was a pop that came from the box over the spindle motor and everything coasted to a stop. The pop sounded like it could have been the top of one of the hexfets on the Pico Systems PWM-servo amp I am driving the motor with. But they look pristine, and all the other components in that box look good and a DVM says they are properly powered. Thinking the motor may have thrown a winding, I've looked it over and checked for shorts and come up empty so far. Back to the 5i25 question. So I fire up the halscope and send it to gpio1.in or in_not. And try to start the spindle from axis with the cable to the bob unplugged. I am seeing a short pulse of 1 volt p-p, which becomes inverted if I look at the in_not, and trying to increase its speed has no effect. So its beginning to look as if I may have blown this 5i25. And I've still no clue what did it. Do you concur, Peter? In that event, I'll need three more, with low profile brackets as I believe the one I was going to run either my toy mill, or this Sheldon lathe, has a bad pin that I was using for the probe, G38.2, and it got flaky. That was because the big dummy I can see in the mirror here forgot to run a decent ground to the frame of my G0704. And it was pretty darned noisy when I put a scope on it. Fixed, but too late for that 5i25. So now I need one for the little monster, one for the Sheldon, and one for my toy mill that I've not found a round tuit to do yet. Thanks Peter, or John T. 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
