Runnable simulator field guide
Jog-run motor PLC scenario: test checklist
Direct answer
The learner can define ownership and priority for jog, run, stop and feedback and prove that mode changes cannot create an unintended maintained command.
Written for pLC learners implementing hold-to-run jog behavior alongside a maintained production run command.
Scenario setup
Jog request, maintained run, stop priority, mode selection, seal-in state, permissives, contactor command, feedback, transition policy and restart state.
I/O and state map
Operator inputs through mode and priority logic to output command, motor response and independent running feedback.
Normal run
Jog operates only while deliberately held, run maintains only under its contract and stop removes both paths.
Boundary run
Simultaneous jog and run, mode change while moving, held button, lost feedback, overload, reset, controller restart and power return.
Injected fault
An input, mode, priority, latch, permissive, command, starter, feedback or restart mismatch.
Target check
The logic embedded in the target machine design and tested with physical controls and protection.
What is the difference between jog and run control?
Jog is commonly hold-to-run for positioning or setup, while run may maintain state until a deliberate stop or other condition removes it.
What should happen if jog and run are pressed together?
The required priority must be explicit and risk-assessed; test the simultaneous case instead of relying on rung order by accident.