PT 100 not working
-
I just installed a new extruder and hotend, which uses a PT100 sensor. This is the first time using a PT100.
After connecting wires, when i start the duetwifi, the current C reading has a pink background and 2000 then the background changes to flashing purple.I have the older PT100 board v0.4. I connected the two PT100 wires to the inner wire terminals on the 4-way of the RTD1 block then connected 1&2, 3&4. I've also tried only connecting the inner wires.
In the config.g file i replaced 305 P1 T100000 B4725 C7.060000e-8 R4700 with 305 P1 X200
Any help would be appreciated.
-
are the pads open or closed on your board?
-
they are open
-
@brian ah so it is expecting a 4 wire config to get around this you can either bridge the pads with solder or use short jumper wires between pins 1 and 2 plus 3 and 4 and connect the PT100 between 2 and 3.
Doug
-
Yes that is exactly what i have done, not the soldering but the other thing.
-
did you do the Troubleshooting part of?
https://duet3d.dozuki.com/Wiki/Connecting_PT100_temperature_sensors#mainand you double checked that you used the right one of the 3 headers and its in the correct orientation?
-
I used the reference page you mention and followed the procedure, my daughter board did not come with the 100Ω resistor so no i didnt do the troubleshooting as described. I have plugged a normal thermistor cartrage into the threaded hole with some extra wire to firm up the connection and that works fine for testing the extruder but of course not suitable for actual printing.
-
can you post a quick pic of your daughter board and wiring please I have an idea but need to see a pic before I comment also make sure the daughter board is sitting correctly on its headers?
-
@dougal1957 Sorry i'm used to drag and drop, dont understand the antiquated methods used here to display a pic, but heres a link to a quick vid https://youtu.be/VGM_1qKaR1g
-
i just switched to rtd2 to see if that would help but no.
-
that looks to be fine to me only thing I can think is that you may either have a faulty port in which case you could try RTD2 and change to X201 or you have wired it up incorrectly it is hard to tell (and very easy to get wrong) if you use the same colour wiring.
It looks like you have taken four wires to the sensor so you need to check that pins 1 and 2 are a pair and 3 and 4 are the other pair.
other than those 2 ideas I am not sure what to suggest
-
@dougal1957 Perhaps a faulty PT100 sensor or daughter board.
-
@brian possible I guess but I would try the other channel first
-
@dougal1957 done that
-
next step I guess is to get a 100 ohm resistor to check the daughter board ports!
-
@dougal1957 where am i going to get that?
-
check the resistance of your pt100 with a multimeter
-
-
ok thanks
