How to test filament sensor?
Hey guys,
I think my filament sensor is funky. I can never get it to go from 0 to 1 when I do the test procedure. Is there a way to test if it is burned out?
To my knowledge it's never been connected incorrectly. Could it possibly be the board? Or should I just go ahead and buy a new sensor and that generally fixes it?
One other question I have, is, will a working filament sensor allow me to change filament mid print if I use octoprint? how is this normally handled when the printer runs out mid print?
Is this still the standard sensor - not the MMU tower?
First check the connection at the Einsy end: pull and replug in case there is contamination.
Blow through the sensor to clear any filament debris.
Does it respond now?
Cheerio,
RE: How to test filament sensor?
If you do not have a MMU, have you checked out this Prusa knowledge base document? https://help.prusa3d.com/en/article/ir-filament-sensor-troubleshooting-mk2-5s-mk3s_112226
Kenn
Quality is the Journey, not the Destination. My limited prints->
RE: How to test filament sensor?
Hey, Yeah I did check the knowledge base document. It worked when I assembled the printer, but then stopped shortly afterwards during use.
I took the whole sensor off the extruder and tried to pass something between its "teeth" which I guess should make it go from 0 to 1, but it stayed on 1 or 0 the whole time (I can't remember which) I used some black PLA filament. Is this is a valid way to test?
Essentially everything mechanically seems ok inside the extruder, the magnets, the balls, the lever etc. I just can't ever get the signal to change no matter what I do. Inserting / removing filament, or removing the sensor and passing the lever or any other piece of material between its sensor surface does not cause the signal to change. I was wondering if I could somehow use a multimeter on the sensor itself, just to check the problem isn't the mainboard detecting the signal rather than the sensor not sending it.
If I fix this, will it enable the printer to use octoprint and stop and reload filament when the filament runs out?
RE:
I took the whole sensor off the extruder and tried to pass something between its "teeth"
This test will only work if done in the dark - one common cause of intermittent sensor issues (not like the ones you describe) is very bright light/sunlight hitting the sensor at an awkward angle.
Yours is more likely to be a connection/wiring issue.
Cheerio,
RE: How to test filament sensor?
Ok, So I just did a quick test.
Printer fully assembled, all lights off in a dark room - IR Sensor shows 1 at all times. With filament or no filament.
If I disconnect the sensor, it shows 0.
What should. I do next? I think the mechanism inside is functioning correctly, but would you recommend perhaps trimming the printed part as per the knowledge base article? Is there a way I can simply remove the IR Sensor and test it with a multi meter to save me disassembling the extruder?
I took the whole sensor off the extruder and tried to pass something between its "teeth"
This test will only work if done in the dark - one common cause of intermittent sensor issues (not like the ones you describe) is very bright light/sunlight hitting the sensor at an awkward angle.
Yours is more likely to be a connection/wiring issue.
Cheerio,
RE: How to test filament sensor?
Ok, with the filament sensor removed but still connected and in a dark room, the IR Sensor still shows 1. I believe this should show 0 - since there is no obstruction for the sensor.
The fact it goes to 0 when i disconnect the sensor makes me believe the sensor is sending a constantly "on" signal, indicating a faulty sensor. I'll try a new one...
RE:
If the LCD is always displaying 1 and the FS is turned on in settings on the printer, that means the sensor is detecting that the beam is blocked. The first thing I would do would be to remove the sensor board and use compressed air to blast the two tiny slots in the sensor("teeth"). Not a brush or cloth! Lung power, while not as effective, is maybe worth a try.
The printer reading zero with sensor disconnect indicates to me that the Einsy board is correctly sensing the state of the sensor output.
Testing a disconnected circuit(with active components) with a mutltimeter is iffy and the results can easily be misleading.
Before ordering a new one, try what Diem suggested, blow out the sensor, but be sure to use compressed air.
Ok, So I just did a quick test.
Printer fully assembled, all lights off in a dark room - IR Sensor shows 1 at all times. With filament or no filament.
If I disconnect the sensor, it shows 0.
What should. I do next? I think the mechanism inside is functioning correctly, but would you recommend perhaps trimming the printed part as per the knowledge base article? Is there a way I can simply remove the IR Sensor and test it with a multi meter to save me disassembling the extruder?
Quality is the Journey, not the Destination. My limited prints->
Go to:
https://help.prusa3d.com/en/guide/how-to-replace-an-ir-sensor-mk3s-mk3s_162262
Look at the second picture of step 4
With a multimeter check the voltage between the Out and +5v lines. The value should change when sensing, Iirc it's 5v for detection but Icbw.
Cheerio,
RE: How to test filament sensor?
This May or may not help
Had a sensor issue, thought I had broken cables or sensor its self.
loosened of the sensor just its holding screw and guess what it worked
Whether it was a loose cable or I had sensor too tight. just thought I would mention it