PT100 sensor and Daughter Board issue



  • Hi,
    Pt-100 sensors showing constant 2000 celsius with no heat supply.
    I am using Duet 2 Wifi 1.04 and Firmware 3.1.1.
    I have Dyze Typhoon Hotend with 2 PT100 sensors on a single hot end. Sensors are 2 wire type. I have connected using Duet Daughter board 1.1 ( RDT Max31865 chipset )
    https://duet3d.dozuki.com/Wiki/PT100_temperature_sensor_daughter_board

    I have setup configuration using Dyze Recommended settings.
    https://docs.dyzedesign.com/typhoon.html#reprap-firmware

    Here the codes:

    ; Heaters
    M308 S0 P"bedtemp" Y"thermistor" T100000 B4138     ; configure sensor 0 as thermistor on pin bedtemp
    M950 H0 C"bedheat" T0                              ; create bed heater output on bedheat and map it to sensor 0
    M307 H0 B1 S1.00                                   ; enable bang-bang mode for the bed heater and set PWM limit
    M140 H0                                            ; map heated bed to heater 0
    M143 H0 S120                                       ; set temperature limit for heater 0 to 120C
    
    M308 S1 P"e0temp" Y"pt1000" R4700                  ; configure sensor 1 as PT1000 on pin e0temp
    M308 S2 P"e1temp" Y"pt1000" R4700                  ; configure sensor 2 as PT1000 on pin e1temp
    M950 H1 C"e0heat" T1                               ; create nozzle heater output on e0heat and map it to sensor 1
    M950 H2 C"e1heat" T2                               ; create nozzle heater output on e1heat and map it to sensor 2
    M307 H1 B0 S0.50                                   ; disable bang-bang mode for heater  and set PWM limit
    M307 H2 B0 S0.50                                   ; disable bang-bang mode for the heater  and set PWM limit
    
    
    ; Fans
    M950 F0 C"fan0" Q500                               ; create fan 0 on pin fan0 and set its frequency
    M106 P0 S1 H2:1 T45                                ; set fan 0 value. Thermostatic control is turned on
    
    ; Tools
    M563 P0 D0 H1:2 F0 S"Typhoon"                      ; define tool 0
    

    The thermistor on board for the heated bed works perfectly. But, within these settings Both PT100 sensors shown 2000 celsius and some open circuit errors.

    Using Duet documentation I have modified the code(HotEnd section) :

    ; HotEnd 
    M305 P1 X200
    M308 S1 P"spi.cs1" Y"rtd-max31865" R4700                  ; configure sensor 1 as PT100 on pin e0temp
    M308 S2 P"spi.cs2" Y"rtd-max31865" R4700                  ; configure sensor 2 as PT100 on pin e1temp
    M950 H1 C"e0heat" T1                               ; create nozzle heater output on e0heat and map it to sensor 1
    M950 H2 C"e1heat" T2                               ; create nozzle heater output on e1heat and map it to sensor 2
    M307 H1 B0 S0.50                                   ; disable bang-bang mode for heater  and set PWM limit
    M307 H2 B0 S0.50                                   ; disable bang-bang mode for heater  and set PWM limit
    M143 H0 S480 ;Set temperature max temp:
    M143 H1 S480 ;Set temperature max temp:
    

    Whatever I have tried using the help of Duet documentation, I could not change the result.
    https://duet3d.dozuki.com/Wiki/Connecting_thermistors_or_PT1000_temperature_sensors

    I have tried with bed Thermistor the daughterboard, values started from the room temperature and keep increased even not heat applied.
    I could not figure out the problem. I appreciate your valuable input and support?
    Kind Regards.



  • @sozkan said in PT100 sensor and Daughter Board issue:

    M308 S1 P"e0temp" Y"pt1000" R4700 ; configure sensor 1 as PT1000 on pin e0temp
    M308 S2 P"e1temp" Y"pt1000" R4700 ; configure sensor 2 as PT1000 on pin e1temp

    you configured pt1000 not pt100

    try

    M308 S1 P"spi.cs1" Y"rtd-max31865" ; configure sensor 1 as thermocouple via CS pin spi.cs1
    M308 S2 P"spi.cs2" Y"rtd-max31865" ; configure sensor 2 as thermocouple via CS pin spi.cs2



  • @Veti said in PT100 sensor and Daughter Board issue:

    @sozkan said in PT100 sensor and Daughter Board issue:

    M308 S1 P"e0temp" Y"pt1000" R4700 ; configure sensor 1 as PT1000 on pin e0temp
    M308 S2 P"e1temp" Y"pt1000" R4700 ; configure sensor 2 as PT1000 on pin e1temp

    you configured pt1000 not pt100

    try

    M308 S1 P"spi.cs1" Y"rtd-max31865" ; configure sensor 1 as thermocouple via CS pin spi.cs1
    M308 S2 P"spi.cs2" Y"rtd-max31865" ; configure sensor 2 as thermocouple via CS pin spi.cs2

    The final value actually the same as your recommendation. The only thing I have now R-value: "R4700".
    "pt100" is not recognised ( temperature display was n/a)

    However, I will try tomorrow again by copying your code.
    Thanks.


  • Moderator

    Please also send M115 to confirm you have firmware 3.1.1 installed.

    Also send M98 P"config.g" to see if there are any syntax errors in your config.g



  • @sozkan said in PT100 sensor and Daughter Board issue:

    M308 S1 P"spi.cs1" Y"rtd-max31865" R4700 ; configure sensor 1 as PT100 on pin e0temp

    Remove R4700, but not sure it will cause a problem.

    Also the jumpers on the board is present?



  • @Phaedrux said in PT100 sensor and Daughter Board issue:

    Please also send M115 to confirm you have firmware 3.1.1 installed.

    Also send M98 P"config.g" to see if there are any syntax errors in your config.g

    @Phaedrux
    This te response from :

    10/25/2020, 12:13:00 PM	M115
    FIRMWARE_NAME: RepRapFirmware for Duet 2 WiFi/Ethernet FIRMWARE_VERSION: 3.1.1 ELECTRONICS: Duet WiFi 1.02 or later FIRMWARE_DATE: 2020-05-19b2
    

    However M98 P"config.g" did not respond from the DWC interface. On the latest beta version was responding and this macro code was working.



  • @bearer said in PT100 sensor and Daughter Board issue:

    @sozkan said in PT100 sensor and Daughter Board issue:

    M308 S1 P"spi.cs1" Y"rtd-max31865" R4700 ; configure sensor 1 as PT100 on pin e0temp

    Remove R4700, but not sure it will cause a problem.

    Also the jumpers on the board is present?

    Thank you all! Temperature issue 99% is solved. 1% is the temperature difference. Which is actually a success. R4700 was the problem! However, in the Duet documentation, this "R4700 " was recommended!

    Heat bed and Hotend temperatures slightly different. I assume PT100 cable length resistance might cause the difference right?
    Here is the result :
    M115.png

    As feedback:
    "S" values sometimes represent the function and Hardware channel and "P" values the same. That is confusing. Am I wrong? There are similar problems with different solutions and it is also confusing.

    As you may look Dyze -Design Typhoon Hotend documentation gives wrong guiding as well...

    By the way, Is it worth upgrading to Board version 3? Because we have plans to integrate a camera onboard, a Realtime printed part simulation that shows work in progress in actual part viewed on-screen display interface using RasberyPi integrated ( if possible) with duet board resources.

    Kind Regards



  • @sozkan
    I will make a conclusion for newcomers especially PT100 or dyze-design Typhoon users.

    • Hardware: Duet 2 Wifi v1.04
    • Daughter Board: v1.1 (max31865)
    • Heat Bed Sensor: an NTC 100k Thermistor connected to the board heat bed connector.
    • Hotend Sensors: 2 Piece of 2 wire PT100 type sensors comes with Dyze-Design Typhoon HotEnd.

    Working Configuratuin Code :

    ; Bed Heater
    M308 S0 P"bedtemp" Y"thermistor" T100000 B4138     ; configure sensor 0 as thermistor on pin bedtemp
    M950 H0 C"bedheat" T0                              ; create bed heater output on bedheat and map it to sensor 0
    M307 H0 B1 S1.00                                   ; enable bang-bang mode for the bed heater and set PWM limit
    M140 H0                                            ; map heated bed to heater 0
    M143 H0 S120                                       ; set temperature limit for heater 0 to 120C
    
    ; HotEnd 
    M308 S1 P"spi.cs1" Y"rtd-max31865"    		 	; configure sensor 1 as PT100 on pin e0temp
    M308 S2 P"spi.cs2" Y"rtd-max31865"             ; configure sensor 2 as PT100 on pin e1temp
    M950 H1 C"e0heat" T1                               ; create nozzle heater output on e0heat and map it to sensor 1
    M950 H2 C"e1heat" T2                               ; create nozzle heater output on e1heat and map it to sensor 2
    M307 H1 B0 S0.50                                   ; disable bang-bang mode for heater  and set PWM limit
    M307 H2 B0 S0.50                                   ; disable bang-bang mode for heater  and set PWM limit
    M143 H1 S480 ;Set temperature max temp:
    M143 H2 S480 ;Set temperature max temp:
    
    ; Fans
    M950 F0 C"fan0" Q500                               ; create fan 0 on pin fan0 and set its frequency
    M106 P0 S1 H2:1 T45                                ; set fan 0 value. Thermostatic control is turned on
    
    ; Tools
    M563 P0 D0 H1:2 F0 S"Typhoon"                      ; define tool 0
    


  • However, in the Duet documentation, this "R4700 " was recommended!

    Only for pt1000? If not please point to where you found it so it can be corrected.

    . I assume PT100 cable length resistance might cause the difference right?

    Could be, use (3 or) 4 wire measurements to eliminate cable lenght as an issue



  • @bearer said in PT100 sensor and Daughter Board issue:

    for pt1000? If not please point to where y

    It is here in the DyzeDesign documentation:
    https://docs.dyzedesign.com/typhoon.html#reprap-firmware
    Dyze.png



  • that is not the official duet documentation.

    the official duet documentation says
    https://duet3d.dozuki.com/Wiki/Gcode#Section_M308_Set_or_report_sensor_parameters

    Rnnn Series resistor value. Leave blank to use the default for your board.



  • @Veti said in PT100 sensor and Daughter Board issue:

    that is not the official duet documentation.

    the official duet documentation says
    https://duet3d.dozuki.com/Wiki/Gcode#Section_M308_Set_or_report_sensor_parameters

    Rnnn Series resistor value. Leave blank to use the default for your board.

    I believe it is Official documentations; R values for the Duet Wifi "R4700" But it did not work with our case. That`s what I mean.
    https://duet3d.dozuki.com/Wiki/Connecting_thermistors_or_PT1000_temperature_sensors#Section_The_M305_M308_R_parameter

    I don`t blame, that's just feedback from the user perspective.



  • @sozkan said in PT100 sensor and Daughter Board issue:

    R values for the Duet Wifi "R4700" But it did not work with our case.

    that is true for the normal thermistor on the duet.
    its not true for the dautherboard.



  • @sozkan said in PT100 sensor and Daughter Board issue:

    I believe it is Official documentations; R values for the Duet Wifi "R4700" But it did not work with our case. Thats what I mean. https://duet3d.dozuki.com/Wiki/Connecting_thermistors_or_PT1000_temperature_sensors#Section_The_M305_M308_R_parameter I dont blame, that's just feedback from the user perspective.

    but that does say PT1000 not PT100; different beasts.

    in any case it should be ammended I guess as the current reccomendation is to leave out R unless you've modified the board or have a very early board. firmware will apply the correct value for a given board - maestro and duet 3 have different value to duet 2 wifi/ethernet



  • @bearer The header starts with; "Connecting thermistors or PT1000 temperature sensors
    The Duet series supports 4 types of temperature sensor: thermistor and PT1000, thermocouple, and PT100.
    "

    Since I don`t see specifically PT100 example, When I see this header, I consider this is a kind of group of sensors.
    "This section describes how to connect thermistors or PT1000."

    isn't it confusing?

    However, it seems like my setup working on the ambient temperature as I share the conclusion, I don`t worry much about what it was saying.
    Thanks for all your contribution.


  • administrators

    @sozkan said in PT100 sensor and Daughter Board issue:

    However, in the Duet documentation, this "R4700 " was recommended!

    Where in the documentation did you see it recommended?

    PT100 documentation is at https://duet3d.dozuki.com/Wiki/Connecting_PT100_temperature_sensors.



  • @dc42 said in PT100 sensor and Daughter Board issue:

    Where in the documentation did you see it recommended?

    https://duet3d.dozuki.com/Wiki/Connecting_thermistors_or_PT1000_temperature_sensors

    The Duet series supports 4 types of temperature sensor: thermistor and PT1000, thermocouple, and PT100.

    maybe that could be re-written to something like

    The Duet series supports 4 types of temperature sensor: PT1000, as well as PT100, NTC thermistor and thermocouple.

    with links to the three other pages, maybe it would be clearer to those not intimately familiar with types of sensors.



  • @bearer said in PT100 sensor and Daughter Board issue:

    @dc42 said in PT100 sensor and Daughter Board issue:

    Where in the documentation did you see it recommended?

    https://duet3d.dozuki.com/Wiki/Connecting_thermistors_or_PT1000_temperature_sensors

    The Duet series supports 4 types of temperature sensor: thermistor and PT1000, thermocouple, and PT100.

    maybe that could be re-written to something like

    The Duet series supports 4 types of temperature sensor: PT1000, as well as PT100, NTC thermistor and thermocouple.

    with links to the three other pages, maybe it would be clearer to those not intimately familiar with types of sensors.

    Right 🙂 Thanks.



  • @dc42 said in PT100 sensor and Daughter Board issue:

    @sozkan said in PT100 sensor and Daughter Board issue:

    However, in the Duet documentation, this "R4700 " was recommended!

    Where in the documentation did you see it recommended?

    PT100 documentation is at https://duet3d.dozuki.com/Wiki/Connecting_PT100_temperature_sensors.

    Thank you very much. That`s exactly what I have done. It seems like working. I will share the youtube video on action.



  • @sozkan said

    Heat bed and Hotend temperatures slightly different. I assume PT100 cable length resistance might cause the difference right?

    • Heat Bed Sensor: an NTC 100k Thermistor connected to the board heat bed connector.
    • Hotend Sensors: 2 Piece of 2 wire PT100 type sensors comes with Dyze-Design Typhoon HotEnd.

    Without knowing exactly where Dyze get their PT100 chips from (and hence what class they are)...

    RTD's (PT100 and PT1000's) are normally laser trimmed, platinum resistors. At room temperature they will typically be accurate to about 0.3 degrees of each other. And they are be read by a chip specifically designed to do that, so it can get better resolution across the usable range of an RTD.
    A Thermistor on the other hand is a much lower quality device, that will probably vary by 2-3 degrees even at room temp, and due to the way it changes resistance, has less resolution at room temp. (Its not unusual for thermistors to vary by up to 20 degrees at 220C).

    As @bearer said, 4 wire sensors would eliminate any error due to cable resistance, but for 3D printing you don't need that level of accuracy.
    The biggest advantage of an RTD is that if you ever replace one, you'll still get the same reading at the same temperature.



  • @theruttmeister Thank you for informative writing.
    I have an extra 8-meter length after the hot end. However, try to make ohmic losses as low as possible by using 0.75 mm cable. It seems like working ( with a 2-3 celsius difference from the Thermistor on the heat bed at room temperature) I also think that`s not an issue.
    B. Regards.


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