Another side filament sensor error
After a good month of working flawlessly my self-build Core one stopped detecting a filament shortage.
Side filament sensor is constantly detecting filament.
Mechanical operation is fine, lever and steel ball are moving when filament is inserted, no magnet sticking out and jamming.
Side Sensor Info says "INS/2" with or without filament installed. Opened up the sensor housing, removed the small circuit board, nothing changed. Only when i disconnected the connector from the circuit board sensor info changes to "disconnected/3".
No specific event as i can remember has gone prior to the sensor misfunctioning.
Main issue i have is that the printer now doesn't stop when the side sensor is detecting a run out of filament, only the main filament sensor in the extruder and by that time it is too late and i cannot change the spool for a new one mid-print.
As i am interested in how things work, how does the small circuit board detects the status of the sensor? I only see a small plastic "bridge" on the circuit board in which a small part of the plastic lever gets inserted between two "jaws". I am familiar witch induction sensors but these don't work on plastic...
Who knows what is going on?
Thanks in advance!
RE: Another side filament sensor error
The sensor is optical, not inductive. The plastic lever only interrupts the light (IR) beam between the LED on one side and the phototransistor on the other side of the U-shaped plastic.
RE: Another side filament sensor error
Ok, thanks a lot, that answers one of my questions.
Anybody knows what can be wrong with the sensor? I do see a lot of replies to this problem but not many anwers.
Maybe contact Prusa and ask to send me a new sensor and/or wiring?
RE: Another side filament sensor error
Ok, thanks a lot, that answers one of my questions.
Anybody knows what can be wrong with the sensor? I do see a lot of replies to this problem but not many anwers.
Maybe contact Prusa and ask to send me a new sensor and/or wiring?
Did you assemble the printer from a kit? With the lever arm attached (with center screw), does it move freely? Make sure the magnet in the arm is not getting caught in the side cover and that the hook of the lever arm move freely in and out of the notch that holds the sensor.
RE: Another side filament sensor error
Yes it was a kit, worked flawlessly for a month, than the sensor was malfunctioning for no reason.
Its mechanically good. Moves freely, no obstruction, no magnet jam....
RE:
For now just disable it. Is it the Core One or Core One+ version? If the later, just turn off the switch. If printer is still under warranty then request support send you a new one.
RE: Another side filament sensor error
Did you re-run the filament sensor calibration? I think it affects both, the hall effect sensor on the print head and the optical side filament sensor. I am not 100% sure and find the schematics of the Buddy extension board to be very poorly labeled -- but I believe that the optical sensor is read via an analog input of the microcontroller and its threshold can be calibrated.
RE: Another side filament sensor error
Remove the small PCB of the sensor again, do not disconnect it and try inserting and removing an opaque piece of material (not paper) into the gap, and watch the reaction on the printer display to see if the status changes. If the status changes between "inserted (ON)" when the gap is free and "removed (OFF)" when there is an object in the gap, the entire sensor is fine and the fault is in the mechanical assembly. If the status does not change, contact support (you will need the printer serial number) and describe the problem. You can even test the entire mechanism by inserting filament into the sensor without the cap mounted, when you will see how the entire sensor works.
RE: Another side filament sensor error
Did you re-run the filament sensor calibration? I think it affects both, the hall effect sensor on the print head and the optical side filament sensor. I am not 100% sure and find the schematics of the Buddy extension board to be very poorly labeled -- but I believe that the optical sensor is read via an analog input of the microcontroller and its threshold can be calibrated.
I think that the sensor calibration is only for the Hall sensor on the Nextruder. The side sensor is a regular optical barrier giving a digital signal 0/1 directly at the output, and there is nothing to calibrate here.
RE: Another side filament sensor error
Thanks again for the input and help.
Is there anyway i can check operation of the sensor and wire loom myself with a multi-meter or something comparable? I am not a very good electrician and i assume i cannot simply measure conductivity in the wires...?
RE:
I think that the sensor calibration is only for the Hall sensor on the Nextruder. The side sensor is a regular optical barrier giving a digital signal 0/1 directly at the output, and there is nothing to calibrate here.
Quite possible; it would make sense. But I seem to recall that the "filament sensor calibration" in the firmware walks you through both sensors. Maybe it's just testing the side sensor, not actually calibrating anything? I can't try right now since I have a long print underway.
As mentioned, I can't make head nor tail of the Buddy extension board schematic. Unless I am overlooking something, it does not even label the connectors for the external sensors, so I can't figure out what the side filament sensor connects to internally.
RE: Another side filament sensor error
The side sensor signal (A_OUT1) comes to the expansion board via the FILAMENT connector, the Hall sensor signal on the Nextruder comes via the love board via the main cable directly to the xBuddy. I just don't know what the door sensor signal (D_OUT2) means on the expansion board schematic, when the existing door connector is connected directly to the xBuddy. After inspecting the expansion board, I discovered another connector on the far left marked EXT and I think it is not used yet. Maybe it is preparation for the top lid sensor or for another purpose in the future and belongs to the D_OUT2 signal.
RE: Another side filament sensor error
The side sensor signal (A_OUT1) comes to the expansion board via the FILAMENT connector
Thanks! I realized that the side sensor is connected to the extension board, and the connector has a "Filament" silkscreen on the board. But how do you know it's the A_OUT1 signal? I don't see the connectors labelled in the schematic.
Does the "A" in "A_OUT1" mean it's an analog signal after all, in contrast to the "D_..." signals?
RE: Another side filament sensor error
A_OUT1 is labeled directly as "A_filament_sensor" in the schematic and it is possible that it is labeled as analog. It is completely common for digital signals to be connected to analog inputs. D_OUT2 is labeled directly as D_door_switch in the schematic. And I don't see any other connector of the corresponding size on the expansion board than the one labeled EXT. And when calibrating, the algorithm looks at the side sensor as OFF/ON while calibrating the sensor on the Nextruder.
RE: Another side filament sensor error
Ah, now I see it -- on the root page of the Extension board schematic. I had gone straight to page 15, "External sensors". There's J2 (connected to A_OUT1) and J3 (D_OUT2) there, with identical connectors and without labels. That's where I got lost. (And still find it bad practice -- I always place text labels in the schematic which echo the silkscreen on the board.)