will be 10,000 i think - they call it "all edges" so it senses 2500 rising edges plus 2500 falling edges and then the same again on the quadrature output so 10,000
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will be 10,000 i think - they call it "all edges" so it senses 2500 rising edges plus 2500 falling edges and then the same again on the quadrature output so 10,000
I've never heard it called edges before, it's normally counts, and for quadrature encoders, it's always four times the slots/lines.
However I have seen various terms used, so if you're unsure, just try the lower figure. Worst case scenario, things only move a quarter what you expect.
Well yes and no really. Yes your 2500ppr becomes 10,000ppr because it's quadrature encoder so 2500 x 4. But in motor tuning you need to divide 10,000 by the pitch of your ballscrew because your entering steps per MM or Inch into tuning.Quote:
Originally Posted by ukmxer
So 10'000 pulses per rev which becomes your steps per revolution in mach3 is divided by say 5mm pitch becomes 2000 pulses per MM.
Just a minor correction, 2500ppr becomes 10'000Cpr.Quote:
Originally Posted by JAZZCNC
Although they're often mixed up anyway, pulse per rev generally refers to the number of pulses each channel produces per rev, which is usually the same as the number of lines, whereas the counts per rev refers to the total number of changes detectable by an encoder counter/reader, which in the case of quadrature encoder is four times the pulses/lines.
Yes noticed after posted didn't put counts but didn't think in this case needed correcting because I gave the figure OP needed.:whistle:Quote:
Originally Posted by m_c
OK, thanks for your help, looks like I have some studying to do.
I have the X axis mounted and working. i set it up using the settings menu,set steps per unit. My mill has its own DRO, so I used that to help me config steps per.
Attachment 23736
Bit of a bodge, but I was not sure it would work, i will make new plates for the X and Y once i have it working.
The backlash is massive at the moment so I will have to adjust that, before I use the machine in anger.
Attachment 23737
I am installing a digital tachometer today. The Varispeed seems way off what it is supposed to be.
I have something wrong somewhere, It would occasionally do a small weird oscillation as if it was looking for its position and would then give an error on the drive.Other than that it was working great.
I have brought my Y axis motor back into the house, so I can play about with mach 3. Its cold in the workshop and a little damp at the moment. I am on with my Y axis motor mount, so time permitting I will have it running in the next two week.
The oscillation is because the drive is struggling to settle and find position the drive then faults because couldn't find position fast eneough. you'll need to play with Gain(PID) settings in the drive. But first I'd check your table is moving freely and the Jibs etc are not too tight.Quote:
Originally Posted by ukmxer
Also you cannot set the PID settings or rather tune the motors on the bench. To do this correctly must be on the machine and working exactly as would in use. By that I mean with all guards, vise's etc permanently on machine while in use so can tune to weight your shifting.
Thanks for your help Jazzcnc.
The jib strips are worn and awkward to set. As soon as I have done the motor mounts the table is coming off so I can put oil feeder lines in, so I will do the jib strips then.
Yes often the case on old Iron. Many people try to tune there way out of sloppy machines but all there doing is stressing motors/drives when good strip down/clean and setup is all that's required.Quote:
Originally Posted by ukmxer
Wouldn't mess around with any PID settings until you have done this and took as much backlash out as possible.
Just installed a tachometer. And it looks like the speeds were out.Attachment 23738