Optical Filament Sensor Problem
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401%?! How is that possible? Does that really mean the sensor is saying 4 times as much filament was used as was requested?
M591 D0 P7 C"e0stop" S1 E50 L1.4 R50:150 A1
M591 D0
Pulse-type filament monitor on pin e0stop, disabled, sensitivity 1.400mm/pulse, allowed movement 50% to 150%, check every 50.0mm, measured sensitivity 1.405mm/pulse, measured minimum 82%, maximum 401% over 94192.7mm -
undefined Phaedrux moved this topic from Using Duet Controllers
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This is using the laser filament monitor with encoder wheel mod?
Firmware version?
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@phaedrux Yes. 3.3.
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I'd try re-assembling the sensor. 4 times the extrusion would mean obvious over extrusion.
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@phaedrux I was looking for confirmation that that's what 401% is supposed to mean. I'm sure it's not actually extruding 4 times the filament. But to figure out what's wrong with the sensor, I need to interpret that number correctly. I was also expressing surprise that, if I AM interpreting it correctly, it would be reporting MORE filament use rather than less (which I'd expect from simple slipping). If I'm understanding the M591 results correctly.
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@donstauffer the amount of movement reported is checked against the amount commanded every "Ennn" mm (in your case 50mm). so with 1.4mm/pulse thats between 35 and 36 pulses.
As its a pulse type sensor I assume it generates pulses both when going forward and backwards? By default movement during retractions is ignored (there is an option in 3.4b6 to not ignore it), however its possible to think of a situation where, with lots of retractions, the same pulse is being sent multiple times as retractions go forward and backwards over a pulse point.
you could test this with a print with no retractions (like a vase mode cylinder), vs one with lots (like a oozing torture test).
