Max Error Temp Error in Build Plate Sensor

[SantiJur 0]

Our UM3 has started with this error after a succesfull print of a ABS piece. Right after we start the printer we get a Build Plate Sensor lecture of 192 °C which is clearly wrong. We tried to move this temp with the wheel, with the GCode and with Cura but we didn´t got any results. Also, we check on the cables in the build Plate and in the main PCB and we didn´t see nothing wrong with that. We tried a factory reset too but the error persists, so we think it could be the PT100 temp sensor. Could you help me out with this or give me tests i could run to check if the PT100 temp sensor is broken? Thank You

Edited June 19, 2017 by Guest

[gr5 1,263]

Can you explain please: is the 192C the goal temp or the reported temp?

If it's the reported temp then the resistance is a bit high.  The resistance should be around 110 ohms at room temp.

192C would imply about 173 ohms.  These parts don't fail but the connection to the pt100 fails easily.  Most likely the problem is where the wiring connects to the print bed.  Check that the two smaller wires are screwed in tight and if so maybe take the bed completely apart (it's not hard - start with removing the 3 leveling screws) and resolder the connections of the terminal block to the circuit board inside the print bed.

Also check the wiring as shown in your photo.

PT100 resistance/temperature conversion table

Edited June 19, 2017 by Guest