Abstract: A switch mechanism senses the rotational direction of a rotating member so that reversal of direction acts through a control switch to energize or de-energize an electric circuit. The mechanism has a reciprocable switch actuator frictionally engaging the rotating member, whereby rotation of the rotating member in one direction pulls the actuator and rotation in the other direction pushes the actuator to operate the control switch. The rotating member may be a shaft, or it may be an idler wheel driven by the shaft, so that the rotational direction of the shaft is sensed and actuates the control switch. Herein, the switch mechanism senses the rotational direction of an output shaft in an escalator drive train. Accidental loss of motor torque when the escalator is in the "up" mode may permit reverse rotation of the output shaft as the escalator starts down under the weight of the passengers, but actuation of the control switch drops the up direction contactor and sets a brake.