2. Installation : mounting to the valveThe ILG/S is a manual override quarter turn gearbox for single acting pneumatic or electric actuators.For maximum allowable input- and outputtorque, refer to table 1 or the (not included) datasheet. This manual describes the installation of the gearbox and its parts. The purpose from the ILG/S gearbox is to open a valve with the gearbox in case of a failing actuator system. If the power supply fails the spring returns the actuator (and valve) to the “secure” (closed) position.