issue with Filament Sensor
First the FS will not autoload my filament has not since I installed the kit. It will unload with no issue.
The Support--> sensor --> IR =1 always.
I have checked the spring tension for the filament which works great, with great prints now.
I removed the sensor to verify the 3 prong cable is corrected. No plastic, dust dirt etc.
I looked down in the sensor hole with no plastic, etc.
Open up the chamber again looking for any debris, nothing.
Open the control circut board with power unpluged to verify the 5 socket connector is connected correctly on the lower 1/2 of the connector with white wire on far left.
Any other suggestions?
Dan
RE: issue with Filament Sensor
The correct behaviour is:
No filament loaded --> FS lever pushed away from sensor by magnets --> unobscured sensor sends ~4.4V signal to Einsy RAMBo board --> board shows IR sensor = 0.
Filament loaded --> FS lever pushed into sensor's gap by ball bearing --> obscured sensor sends ~0.4V signal to Einsy RAMBo board (0.0V on sensors version 0.3 or lower) --> board shows IR sensor = 1.
A sensor value of 1 at all times implies that your filament sensor is stuck in the second condition even when the filament isn't loaded. Off the top of my head, the two most obvious causes are:
- Dirt in the sensor gap.
- Screw on the FS lever too tight (it needs to be tight enough to stop the lever wobbling around, but the slack needs taking off a tiny bit so it can move without friction).
- Magnet in the FS lever wrong way round (magnets should repel the lever, towards the ball bearing).
- Magnets not fully seated into their holes, rubbing on the extruder body (i.e. lever works when extruder case open, jams when screwed together).
- Malformed filament sensor lever obscuring sensor even when in the off position.
- Faulty sensor sending no voltage to Einsy RAMBo, interpreted as a "1" signal (Note: if using a filament sensor v0.4 or newer which are the only ones ever made from a red PCB, and using MK3S firmware v3.9.0 or newer, the printer can be made to detect the difference between faulty sensor and no filament loaded as the newer sensors give a tiny voltage even when obscured, see the filament sensor recognition section in page https://github.com/prusa3d/Prusa-Firmware/releases/tag/v3.9.0 )
My MK3S from over a year ago had (5) wrong with it on arrival, which I didn't notice until I got a filament runout. Prusa support sorted this out.
RE: issue with Filament Sensor
The "s" design is very finicky with the sensor. The "s+" was redesigned to be more forgiving.
I needed in loosen the cap piece over the sensor and fiddle with the sensor board position to get it right. I, along with others, have had to put shims under the sensor board to get it to work reliably.
RE: issue with Filament Sensor
I have one printer where the reliability of the sensor section is hit and miss.
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Chuck H
3D Printer Review Blog
RE: issue with Filament Sensor
hello for me the problem comes from the old FS-cover part:
if you measure the length of the spare for the FS-sensor board you'll find something
of ~22mm
When you measure the length of the FS-sensor board you'll find something
of ~26mm.
So the FS-Cover hits/presses on the FS-sensor board on the last 4mm.
If you press the FS-sensor board in this area with a wooden toothpick you'll find the FS-sensor status changed.