Machine limit. Old geared machines
Rotation of machine activates it.
Open/lockout mainline, remove cover.
It'll probly be a coarse thread with follower driven at same rpm as driver.
A few ways to make it open, most common that it travels too far, hits dog, rotates, opens circuit.
Adjustable. Make sure it activates before any collision.
Requires service that will be obvious when you see it.
We used to jump out with heavy jumper cables or chunks of carbon.
Normally would be in series with mainline/motor leads.
