Mosquito Hotend PT1000 issues

dc42

@wcmartino do you have a multimeter? If so, disconnect the PT1000 cable at the Duet and measure its resistance.

wcmartino

@Phaedrux I have two of them and they are both pt1000's, very hard to read but it is stamped on the part. Tried both plugged directly into the Duet with the same results.

@dc42 Measured the resistance at the connector going into the Duet and my spare PT100, at room temp they are reading about 1.1k ohms, which is about what I expect.

Phaedrux

@wcmartino said in Mosquito Hotend PT1000 issues:

Tried both plugged directly into the Duet with the same results.

Did you change the config to suit?

Does the spare PT1000 work on the Duet?

dc42

@wcmartino yes 1.1K at room temperature is about right.

Please post a photos showing how the Pt1000 is connected to the Smart Effector, and how the Smart Effector is connected to the Duet.

wcmartino

@Phaedrux Yes I changed the config to suit. I get the same results with the spare PT1000.
@dc42 Pictures attahced.

dc42

@wcmartino it's not entirely clear from your photos, but it looks to me that you have 2 black wires in the cable(s) between the Smart Effector and the Duet. One is carrying one of the PT1000 wires, the other is carrying the ground connection to the Smart Effector. Is it possible that you have those wires crossed?

Can you try connecting your spare PT1000 directly to the TEMP2 connector on the Duet in place of the cable from the Smart Effector?

wcmartino

@dc42 I tested both PT1000 on the effect and directly on the board. They both show the same issue. Everything works fine with an e3d thermister, have had this printer for years. When I get a mintue I might try and plug them into my 6HC on my CoreXY and see what it shows. Kind of at a loss.

dc42

@wcmartino it might be worth running temperature input calibration. See https://docs.duet3d.com/en/User_manual/Connecting_hardware/Temperature_connecting_thermistors_PT1000#semi-automatic-calibration.

wcmartino

@dc42 That made no difference. The current Duet Mini 5+ was a rev0.5, which was working fine with the e3d thermistor. I have a new Mini that I just ordered for a different project, so I swapped them out and it is working just fine now. Makes me question if the old Mini is broken and it has not worked right for a while.

dc42

@wcmartino did you move the SD card from the original Duet 3 Mini to the new one, or did you use a new SD card? If you used a new SD card then perhaps there is something in the config.g or config-override.g file on the original SD card that was affecting the reading and overriding the calibration, such as a H or L parameter in the M308 command for that sensor.

wcmartino

@dc42 I am in SBC mode so nothing changed between the configurations. It is possible there is just something wrong with the older board.

dc42

@wcmartino I doubt it, however they will probably need different ADC corrections. Your new board will have had the calibration done and stored during testing; your older board will not. That's why I suggested you perform the calibration. PT1000 sensors are more sensitive to calibration errors than thermistors. Are you sure that you performed the calibration correctly on the older board?

wcmartino

@dc42 Yes, tried it several times, nothing helped for either sensor. Will have to revist it antoher day, I already have the printer put back together.

dc42

@wcmartino what L and H corrections did the calibration process report?

wcmartino

@dc42 Ok reconnested the board. With the sensor disconnected H reports -6. Jumpering the connector on the effector and running the l999 says correction is 1.

With the resistor in place upon booting it shows -20.5C. If I manually set H to -127 I still show -15.3C.

dc42

@wcmartino have you tried using a different temperature input?

wcmartino

@dc42 Appoligies for the delayed response. I get the same results. I am good with running the nerw board on the Delta.

dc42

@wcmartino when and where did you purchase the original board?

wcmartino

@dc42 I purchased the board from Fliastruder way back in Dec 2020.

dc42

@wcmartino unfortunately it's out of warranty then. As the calibration process produces sensible L and H values, it appears that the ADC is working correctly. You could use your multimeter to check that the thermistor series resistors R60 R61 and R62 read correctly. They should each read 2200 ohms with nothing connected to the TEMP pins.