Method for operating an elevator for maintenance

A method for operating an elevator for maintenance, the elevator including a car displaceable along an elevator shaft, a drive displacing the car, a plurality of shaft doors, at least one of the shaft doors being arranged at each of multiple floors along the elevator shaft including a lowermost floor and an uppermost floor, and an elevator control unit controlling the elevator in a normal operation mode or in a maintenance mode, the method comprising the steps of:

• receiving by the elevator control unit a start-maintenance-request sent by a first entity, wherein the first entity is a first technician using an assigned first mobile electronic device to send the start-maintenance-request;
• the elevator control unit switches from the normal operation mode to the maintenance mode in response to the start-maintenance-request;
• the elevator control unit assigns a maintenance token to the first entity;
• after completing the preceding steps, performing the following steps in order;
• receiving by the elevator control unit a reassignment-request sent by a second entity, wherein the second entity is a second technician using an assigned second mobile electronic device to send the reassignment-request;
• wherein the elevator control unit checks whether a person is within a predefined danger zone in the elevator shaft;
• the elevator control unit assigns the maintenance token to the second entity;
• receiving by the elevator control unit a stop-maintenance-request sent by the second entity using the second mobile electronic device;
• and
• the elevator control unit switches from the maintenance mode to the normal operation mode in response to the stop-maintenance-request.