Hi,

The SFC operates according to ISA88. See attachment for the Operating State Logic.

The Hold/Resume/Abort/Reset are commands and the sequence goes to transitional states and then to steady states for example from Run to Holding (transitional) to Held (steady).

For example: If you initiate a Hold command, the SFC goes to Holding and then to Held. You can program sequencers in the SFC, for example if holding is active. Then the SFC will execute the steps in the holding sequence. If you do not program anything, the SFC still goes to holding, but does not execute any steps.

Reset is used to reset the SFC to Idle from a steady state like Completed/Aborted.