intermittent IR probe problem

balex29

Sometimes when I home the z axis it crashes the nozzle into the bed
If I do a firmware reset via the web interface it still happens
If I turn off at the mains and back on the ir probe works correctly
When it crashes the led lights to show it is triggered but it does not stop and then raise the axis but plows on down
It is not a regular occurrence so I do not thing it is a setup problem

any ideas/suggestions welcome

Rob H

dc42

Assuming you are using the IR sensor with Duet electronics, please post your config.g file.

balex29

hi
sorry for delay
I have a duet wifi and run an ending script -
G1 E-1 F300 ;retract the filament 1mm
G1 Z+10.0 E-3 X-20 Y-20 F6000 ;move Z up and retract filament 3mm
M106 S255 ;fan at 100% to cool nozzle
G90 ;absolute positioning
G28 X0 Y0 ;home X and Y
G1 Y190 ;move bed forward
M84 ;steppers off
G4 P200000 ;wait (200 seconds)
M106 S0 ;fan off
if this runs every so often but not every time the ir probe does not trigger when I home the axes again
a firmware reset does not re enable the probe
only a power down and switch back on does
firmware 2.02RC4(RTOS) (2018-11-18b5)
web server 1.21
web interface 1.22.5
config.g (needs tidying up)
; Configuration file for Duet Wifi with V1.20 firmware

RCH 3D printer

; Communication and general
M111 S0 ; Debug off
M550 PRCH 3D ; Machine name and Netbios name (can be anything you like)
M551 Pzander09 ; Machine password (used for FTP)
;M540 P0xBE:0xEF:0xDE:0xAD:0xFE:0xED ; MAC Address
M552 S1 ; Enable network
M586 P0 S1 ; Enable HTTP
M586 P1 S0 ; Disable FTP
M586 P2 S0 ; Disable Telnet
M555 P2 ; Set output to look like Marlin
M575 P1 B57600 S1 ;paneldue

; Axis and motor configuration
M569 P0 S1 ; Drive 0 goes forwards
M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S0 ; Drive 2 goes backwards
M569 P3 S0 ; Drive 3 goes backwards
M569 P4 S1 ; Drive 4 goes forwards
M350 X16 Y16 Z16 E16 I1 ; Set 16x microstepping with interpolation
M574 X1 Y1 Z0 S1 ; set endstop configuration
M906 X800 Y1000 Z800 E800 ; Set motor currents (mA)
M201 X800 Y800 Z150 E1000 ; Accelerations (mm/s^2)
M203 X6000 Y6000 Z180.00 E1200.00 ; Maximum speeds (mm/min)
M566 X600 Y600 Z30 E250 ; Maximum jerk speeds mm/minute
M92 X79.80 Y79.80 Z403 E420 ; Set axis steps/mm
M208 X0 Y0 Z-0.5 S1 ; Set axis minima
M208 X270 Y275 Z400 ; Set axis maxima
G21 ; Work in millimetres
G90 ; Send absolute coordinates...
M83 ; ...but relative extruder moves

;M307 H3 A-1 C-1 D-1 ;
;M558 P5 X0 Y0 Z1 H5 F100 T2000
;G31 X0 Y0 Z0 P25
;z probe
M558 P1 X0 Y0 Z1 ; Z probe is an IR probe and is not used for homing any axis
G31 P500 Z1.00 ; Set Z probe trigger value, offset and trigger height
;M558 P1 I0(or I1) R0.4 F300 X0 Y0 Z0
;G31 X0 Y0 Z-0.1 P600

; Thermistors
M305 P0 T100000 B3950 R4700 H30 L0 ; Put your own H and/or L values here to set the bed thermistor ADC correction
M305 P1 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set first nozzle thermistor ADC correction
; M305 P2 T100000 B3974 R4700 H30 L0 ; Put your own H and/or L values here to set 2nd nozzle thermistor ADC correction

; Tool definitions
M563 P0 D0 H1 ; Define tool 0
G10 P0 S0 R0 ; Set tool 0 operating and standby temperatures
;*** If you have a single-nozzle build, comment the next 2 lines
;M563 P1 D1 H2 ; Define tool 1
;G10 P1 S0 R0 ; Set tool 1 operating and standby temperature

thanks
Rob H

Edkirk

My IR probe has worked flawlessly until I raised the window curtain and sun shined on the bed - - - problem went away when removed from direct sunlight.

dc42

@balex29, are you by any chance running an Ormerod, or some other printer that uses the IR sensor for doing something other than jst Z probing, e.g. homing the X axis?

I mention this because at one time the standard homing files published by RepRapPro used a G31 P command to change the IR sensor threshold in some cases - I think it was in the homex.g file. If the LED on the IR sensor lights up but the Z axis does not stop, this suggests to me that the G31 P value may have been changed from the value of 500 that must always be used with the differential IR sensor.

You can check the current value of the G31 P parameter (trigger threshold) for probe type 1 by ending G31 T1.

balex29

Hi
I have a cr-10 converted to duet - micro switches for x and y ir probe for z
the problem occurs only occasionally when a print finishes and the printer runs the end script - when I home the axes the ir probe fails to trigger - ie no led light up and crashes into the bed only a power down sort this out

Rob

dc42

@balex29 said in intermittent IR probe problem:

Hi
I have a cr-10 converted to duet - micro switches for x and y ir probe for z
the problem occurs only occasionally when a print finishes and the printer runs the end script - when I home the axes the ir probe fails to trigger - ie no led light up and crashes into the bed only a power down sort this out

In your original post you said:

When it crashes the led lights to show it is triggered but it does not stop and then raise the axis but plows on down

which I took as meaning that the LED on the IR sensor does light up, but the probe doesn't stop descending. So which is correct: does the LED on the IR probe light up, or not?

Also, how come you are homing Z when there is a print on the bed? Are you moving the head off to one side when homing Z at the end of a print; and if so, is the IR sensor off the edge of the bed when you do this?

balex29

sorry let me clarify
The ir probe does not come on when it crashes
I have waited for the printer to run ending script and then remove printed part
I start a new print then occasionally but not ever time the head crashes when it homes at the start of the print it also happens if I home the axes but not every time but once it does this even a firmware reset does not stop it crashing only a power off and then on

Rob H

dc42

@balex29 said in intermittent IR probe problem:

sorry let me clarify
The ir probe does not come on when it crashes
I have waited for the printer to run ending script and then remove printed part
I start a new print then occasionally but not ever time the head crashes when it homes at the start of the print it also happens if I home the axes but not every time but once it does this even a firmware reset does not stop it crashing only a power off and then on

Rob H

If a power off/on always solves it and a software reset (or pressing the reset button) never does, that sounds like the firmware on the IR sensor has crashed. That's odd, because it uses a watchdog to detect and recover from a firmware crash (although I have never seen that happen - the tell-tale would be the 4 flashes of the LED), and nobody else has reported a similar problem. So I think your IR sensor has a faulty microcontroller. If it is still under warranty, please ask for it to be repaired or replaced.

balex29

hi
thanks for looking at the problem I have several IR probes and I have changed out the one giving me problems - so I will see if problem occurs with new one and let you know if it does
Rob H

balex29

ps thanks for great support on this forum it is really appreciated

Rob H

balex29

HI
solved the problem changed out sensor and all worked fine
then put old ir probe back and problem recurred - so appears to be a faulty probe ansd with new probe found printing is better - maybe erratic homing with old sensor?

Rob H