The Safety Output Torque Limiter (SOTL/ATT) is a safety device manufactured by Italplant for placement on the motor's input shaft. The limiter makes use of the Italplant-patented SOTL system, designed for protecting machines and operators from "jamming" of the body against the dial plate.
The limiter is positioned at the opening of the gearbox, serving only to protect the main organ transmission, the indexer, and its cam followers, which are the weakest indexer parts. This does not protect the machine nor the people in contact with the stations.
Safety of the input shaft in the gearbox is only brought about by the indexer during instances of panic stops and machine restart, in an operating stage involving equal coefficients of maximum acceleration and the law of motion indexer.