The Limited qualifier activates an action output immediately but automatically turns it off after a specified duration.
Think of L as a time-limited version of N. The output is active for at most the specified duration, but never longer than the step itself.
{GIF:HERE} - Step properties panel showing the action 'Buzzer alert' with qualifier dropdown set to 'L' (Limited) and duration field set to 3000 ms
from automation_machine import ActionQualifier
step.add_action("buzzer", "Buzzer alert", qualifier=ActionQualifier.L, duration=3000)
The duration parameter is required and specifies the maximum active time in milliseconds.