Configuring PT1000 sensors

[Dougal1957]

This is probably for David but please feel free to chip in if you can help.

I Have some PT1000 sensors from RS pn 100-7530 https://uk.rs-online.com/web/p/platinum-resistance-temperature-sensors/1007530/?sra=pstk and I have put one straight into a molex shell for test.

when out of the board it measures 1.1 kOhms so I would expect this to give me a sensible reading on DWC (Not the case)

I have it configured as M305 P0 X500 in my config

with nothing connected to the E0 Thermistor pins the DWC Reads 493.6 degrees with the pt1000 connected I get the same

This is the Heater section of my Config.g

; Heaters
M305 P0 X500 R4700 ; Configure thermocouple for heater 0
M143 H0 S120 ; Set temperature limit for heater 0 to 120C
M305 P1 X200 ; Configure thermocouple for heater 1
M143 H1 S280 ; Set temperature limit for heater 1 to 280C

I am on the latest FW

Any ideas what I have done wrong

Doug

[DjDemonD]

Hi Doug,

I have some sample pt1000's that we are about to begin stocking. I just measured one and it shows 1.035Kohm at about 14 degrees C.

I have got 3 connected to my cylinder delta using the following config

M305 P0 X500 R4700  			; heater 0 uses a PT1000 connected to thermistor channel 0 which has a 4.7K series resistor
M305 P1 X501 R4700  			; heater 1 uses a PT1000 connected to thermistor channel 1 which has a 4.7K series resistor
M305 P2 X502 R4700  			; heater 2 uses a PT1000 connected to thermistor channel 1 which has a 4.7K series resistor

So it might be the heater channel has to be 501,502,503 etc…

[dc42]

Your M305 comments don't match the parameters values. Your first M305 command says that the bed heater channel uses a PT1000 connected to the bed thermistor input. The second one says that your E0 heater uses a PT100 sensor connected to a daughter board. Nothing about a PT1000 connected to E0 thermistor input.

[Dougal1957]

no this is for the bed Simon I intend to use a PT100 in the hotend

I have tried X501 for P1 as well with the same results. also with and without the R4700

[Dougal1957]

Thank you David that was the Clue I needed all now sorted.

I did indeed put it on the E0 thermistor input instead of the bed one Doh

Doug