Thermocouple errors out on faulty 2000C reading

AntonVE

I have a duet ethernet (v1 firmware 1.2) and i have the official duet thermocouple daughterboard (the one without jumpers or solder pads) and use a type k thermocouple.
It works great and gives a good accurate reading, but for some reason on start up it sometimes reads 2000°C.
Usually just restarting the board/power fixes this. However while printing it reads just fine but sometimes spikes to 2000°c making the printer run an error and stops. There is no time frame this happens sometimes few minutes in, sometimes half hour in.
There is no way to reproduce the behavior, not by fiddling the wires, fiddling with the head, pulling, pushing nothing....
Any ideas why this happens?

SIam

it sound as a thermal problem is it right when the printer is cool you have more problems as when it is hot?
maybe it is a cold soldering point on the thermocouple board ?

dc42

@AntonVE said in Thermocouple errors out on faulty 2000C reading:

I have a duet ethernet (v1 firmware 1.2)

It sounds that you are running old firmware. Please upgrade to firmware 2.05 and test again. If the error happens again, send M305 P# where # is the heater number. This will tell you the last error reported when trying to read the thermocouple.

AntonVE

@SIam i am sorry for the late replay i thought i had notifications enabled which i apparently didn’t and forgot to check back in till today.

thanks for your replay!
It doesn’t matter if the machine is cold or warm. When i start/reset it it sometimes jumps to 2000°c with no apparent clue of why it happens. It doesn’t matter wether the machine is warmed up or completely cold, if i restart the machine i think 3 times out of 10 it starts with 2000°c reading.
I don’t mind that behavior too much, it is the sudden crashing while printing that bothers me. Sometimes it is a minute into printing sometimes it is after 30mins and have not gotten past 30minutes without the error.

I will try what the next reply suggests and upgrade the firmware and check if that helps.

AntonVE

@dc42 i am sorry for the late replay i thought i had notifications enabled which i apparently didn’t and forgot to check back in till today.

thanks for your reply!

I will check to upgrade the firmware.
It was to my understanding i could not upgrade to v2 with this board, i am glad to find out i am wrong.
Will let you know once updated if the error persists.