Thermal runaway
I was pre-heating for ABS when at about 90% temperature the temp suddenly read 24 degrees and the fan stopped. The extruder was very hot but still reading 24 degrees. I switched off and started pre-heat again - same thing - hot end very hot but low temp reading.
I switched the thermisters over on the circuit board and the temperatures read as they should albeit reversed around. This proved that the thermisters were working. When I put the leads back to their original positions everything started up normal.
This is the second time this has happened. The two thermister cables were plugged securely into the board and are clicked into place. It sounds like a firmware issue as the hardware seems to be ok.
Any help on this please.
John
Re: Thermal runaway
This most likely is not firmware related but rather a loose contact in the thermistor cable.
Presumably somwhere near where it gets bent when moving.
What you are describing is exactly how that begins.
Heat your extruder and wiggle all those cables back and forth.
Eventually you will see the temp drop.
Don`t worry, this will get worse with the time and the faulty point easier to locate..