The invention concerns an arrangement and a method for controlling the power supply of the load of an elevator system. The arrangement has at least a monitoring unit and at least one controllable power source. The controllable power source is connected between the load of an elevator system and the monitoring unit such that the power supply of the load of the elevator system can be controlled by means of a control signal transmitted to the controllable power source by the monitoring unit. The monitoring unit according to the invention contains at least one input for determining the status of at least one safety switch of the elevator system. On the basis of the status of the safety switch a control signal either having pulses or being in a static state is sent with the monitoring unit to at least one controllable power source.