The pinsetter is either "on" or "off", there are no other states to manage. Once it's on, it runs indefinitely: it sets the pins, clears the alley, resets the remaining pins, and repeats the cycle, all without any external control.

On mine, I do have some "feedback info" on which pins are down + a signal to "when" to score points, but this is optional as you can also write your score manually if you have no scoring computer system.

That one relay is the only connection between the pinsetting machine and the scoring system.

> Can you explain the significance of the single relay? My car starts with a single solenoid.

Your car also starts with a single relay... that drives a solenoid and a motor.

Yeah this $100k system with all its expensive add ons is there to push a single button.