PT-100 temperature constantly at 2000 degrees after failure

CoolM8

I don't see anything that any of the circuit traces are broken nor does anything look damaged.

With the reprapfirmwar tool i get this config for the E3D thermistor:

[[language]]
M305 P1 T100000 B4725 C7.060000e-8 R4700 X201 ; Set thermistor + ADC parameters for heater 1 and remap it to channel 201

But i also tried everything else even:

[[language]]
M305 P1 X201

dc42

Do you have the PT100 connected to the first or second channel on the daughter board? 201 is the second channel, the first is 200.

CoolM8

Right now i have on the second channel. As I've said, it used to work on channel 1 until the failures and since then it doesn't even work on channel 2.

dc42

Do you have a resistor of between 100 and 200 ohms that you can connect to the terminal block in place of the PT100?

CoolM8

No i don't have a resistor around but i think this won't make a difference. Since the Ultimaker Original has a measurable resitance of around 100ohms. It measures like in the image below (the green connection has around 110 ohms):

It seems to me that the issue is with the daughter board or the duet itself.

dc42

Do you have anything else connected to the SPI bus, for example a ribbon cable connecting the CONN_SD port on the Duet to the PanelDue for using a second SD card?

If the answer is no, please ask your supplier for a new daughter board.

CoolM8

Well, I've ordered a new daughter board but i still get the same issue. And no I've nothing connected to SPI bus. There is no PanelDue nor a second SD card.

dc42

Have you removed the PT100 sensor from the hot end or is it still installed? I'm wondering whether it may have developed a short between the element and the case.

CoolM8

It's the same even if installed in the hotend or not. If I read the voltage on the middle 2 pins I get a reading of about 2V with the E3D PT100 and about 0.2V for the Ultimaker PT100. With both those voltages i get 2000 degrees in the Frontend.

dc42

The 0.2V with the Ultimaker sensor sounds plausible, the 2V with the E3D one sounds like an open circuit sensor, or else it's a thermistor not a PT100.

If you send the M305 P1 X201 command from the Gcode Console, does it return an error message?

CoolM8

It is all fine when I send M305 P1 X200 or X2001, no error message whatsoever. It even turns off the fan shortly that is set to start at 40 degrees but that runs continuously now because of the 2000 degrees.

dc42

What voltage do you read across the outer 2 pins of the 4 pin terminal block? It should be the same 0.2V that you get across the inner ones, with the good PT100 connected.

CoolM8

Yes the outer 2 pins show 0.2 V as well. I really don't get this, why did it used to work and now nothing helps? There is nothing burnt or damaged on the duet itself.

dc42

My best guess is that the SPI bus isn't working but I'm puzzled that there is no error message. Do you have anything connected to the expansion connector?

CoolM8

Still no, as I've already said.

dc42

I suggest you ask your supplier to replace the Duet.

CoolM8

Well, I've gotten the replacement for the DuetWifi, but since i haven't seen any damage at my previous DuetWifi I haven't had big hopes and thats exaclty what it tourned out. No luck and everything is still the same, giving me a reading of 2000 degrees. I have even tried the solution from here: https://miscsolutions.wordpress.com/2016/06/25/more-delta-printer-upgrades-wifi-and-silence/.
There was also the E3D PT100 sensor used and 4 wires were connected to the sensor wires.
Now everything is new: the duet, the daughter board & the PT100, so it must be the configration. I have tried the following configs:

M305 P1 X200 (E3D and Ultimaker PT100)
M305 P1 T100000 B4725 C7.060000e-8 R4700 X200 (E3D PT100 only)
M305 P1 X201 (E3D and Ultimaker PT100)
M305 P1 T100000 B4725 C7.060000e-8 R4700 X201 (E3D PT100 only)

what else could be the issue here?

deckingman

Maybe it's because you've set P1 to use both channels (X200 and X201). If you've only got one PT100 and it's used on the hot end, all you need is M305 P1 X200. If you are using 2 PT100s, one for the bed and one for the hot end, then you have something like M305 P0 X200 and M305 P1 X201. You don't need the thermistor and ADC parameters for a PT 100 but those lines probably just get ignored.

Dougal1957

Can you post your full Config.g file wonder if there is a line after the M305 that may be overriding it?

Doug

Ian I think the op has tried all those lines one at a time to try and get to the bottom of the issue not all at the same time

CoolM8

The strange thing is that it used to work before until it failed in the beginning of a print. Since then i only fiddled around with the M305 P1 command.

[[language]]
; Configuration file for Duet WiFi (firmware version 1.17)
; executed by the firmware on start-up
;
; generated by RepRapFirmware Configuration Tool on Wed Apr 19 2017 22:18:05 GMT+0200 (W. Europe Daylight Time)

; General preferences
M111 S0 ; Debugging off
G21 ; Work in millimetres
G90 ; Send absolute coordinates...
M83 ; ...but relative extruder moves
M555 P2 ; Set firmware compatibility to look like Marlin
M208 X0 Y0 Z0 S1 ; Set axis minima
M208 X205 Y205 Z205 S0 ; Set axis maxima

; Endstops
M574 X1 Y1 Z1 S1 ; Define active high microswitches
M558 P0 X0 Y0 Z0 H5 F120 T6000 ; Set Z probe type to switch, the axes for which it is used and the probe + travel speeds
G31 P600 X0 Y0 Z0 ; Set Z probe trigger value, offset and trigger height
M557 X15:190 Y15:190 S20 ; Define mesh grid

; Drives
M569 P0 S1 ; Drive 0 goes forwards
M569 P1 S1 ; Drive 1 goes forwards
M569 P2 S1 ; Drive 2 goes forwards
M569 P3 S1 ; Drive 3 goes forwards
M350 X16 Y16 Z8 E16 I0 ; Configure microstepping without interpolation
M92 X157.4804 Y157.4804 Z533.3333 E832 ; Set steps per mm
M566 X1200 Y1200 Z480 E120 ; Set maximum instantaneous speed changes (mm/min)
M203 X8100 Y8100 Z1200 E1200 ; Set maximum speeds (mm/min)
M201 X500 Y20 Z250 E250 ; Set accelerations (mm/s^2)
M906 X1100 Y1100 Z1100 E1100 I30 ; Set motor currents (mA) and motor idle factor in per cent
M84 S30 ; Set idle timeout

; Heaters
M143 S310 ; Set maximum heater temperature to 310C
M301 H0 S1.00 P10 I0.1 D200 T0.4 W180 B30 ; Use PID on bed heater (may require further tuning)
M305 P0 T10000 B3988 C0 R4700 L0 H0 ; Set thermistor + ADC parameters for heater 0
M305 P1 X200

; Tools
M563 P0 D0 H1 ; Define tool 0
G10 P0 X0 Y0 Z0 ; Set tool 0 axis offsets
G10 P0 R0 S0 ; Set initial tool 0 active and standby temperatures to 0C

; Network
M550 PUltimaker ; Set machine name
M552 P0.0.0.0 S1 ; Enable network and acquire dynamic address via DHCP

; Fans
M106 P0 S1 I0 F500 H1 T45 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned on
M106 P1 S1 I0 F500 H-1 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned off
M106 P2 S1 I0 F500 H-1 ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned off

; Custom settings are not configured