No program on the controller!
Safety CPU Boot Failure / No Program Loaded
ABB · AC500 Function Block Libraries
What does No program on the controller! mean?
The safety CPU fails to enter RUN mode after power-on, with the DIAG LED on and no boot project loaded. This often occurs if the power-off to power-on pause is less than 1.5 seconds, triggering a power dip detection that prevents the existing boot project from loading.
Source: ABB AC500 Function Block Libraries
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