Running my Ultrabase (glass plate) through a MOSFET on an stock A8 board with Marlin 1.1.8. When I do PID tune through Pronterface (by using the
M303 E-1 C8 S70 command) the bed heats up no problem and completes the tune, but when printing from SD or using the Preheat PLA command on the printer to heat the bed, nothing happens and then I get "Bed heating failed".
As its working through Pronterface I know the wiring is okay.
Anet A8 Stock Board
Ultrabase 220x200 12v
PID Values extracted from Pronterface Via
M303 E-1 C8 S70 from cold bed
Message take about 1 minute to appear, seems to be a timeout as opposed to an instant error
Disabling PIDTEMPBED and enabling MAX_BED_POWER resolves the issue allowing the printer to heat the bed
Thermal protection for bed set to
#define WATCH_BED_TEMP_PERIOD 180 // Seconds #define WATCH_BED_TEMP_INCREASE 2 // Degrees Celsius
When using PIDTEMPBED the LED on the bed does not light, but when using MAX_BED_POWER / PIDTUNE it does