PEERPSI Posted October 4, 2012 Share Posted October 4, 2012 Based on the example for Ixx71 below I calculate my counts to be 30.48 mm/cycle*line/.0001379*128 counts/line=28291806 which is more then 11,000,000 then the maximum allowed per variable range limits. My hardware is Turbo PMAC2 Clipper, ACC-51S interpolator, scale with a .1379 micrometer period and my motor has a 30.48 pole pitch. What are my options? Ixx71 Motor xx Counts per N Commutation Cycles Range: 0 – 16,777,215 Units: counts Default: 1000 2. A linear motor has a 60.96-mm (2.4-inch) electrical cycle. An encoder with a 40 micron pitch is wired directly into PMAC and “times-4” decode is used. Ixx70 can be set to 1 and Ixx71 can be calculated as: Ixx71=60.96mm/cycle*line/.04mm*4 counts/line=6096 counts/cycle Link to comment Share on other sites More sharing options...
tahoe brian Posted October 4, 2012 Share Posted October 4, 2012 I might be wrong (I have had my head up my a** all day), but I think your encoder is 128 nanometer line pitch, and with x4 decode your hardware pitch is 32 nanometers. So for a 60.96mm motor pitch, you have 60960000 nm / 32 nm = 1,905,000 hardware counts per cycle. As your example that you posted says, the commutation routine ignores the intepolated counts and only uses the "hardware" counts Link to comment Share on other sites More sharing options...
PEERPSI Posted October 4, 2012 Author Share Posted October 4, 2012 137.9 nm pitch I was using the fully interpolated counts when I should have been using the hardware counts. I'm learning! Thanks all! Link to comment Share on other sites More sharing options...
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