Elevator system for controlling response to call

An elevator system for controlling a response to call, comprising:

• a call button for calling an elevator car;
• a response lamp for responding to the elevator call by the call button, and for displaying service availability of the elevator car;
• a plurality of sub-controllers connected to the call button and the response lamp, for determining service availability of the elevator car responding to a call when the call is generated by the call button, and for controlling an ON/OFF operation of the response lamp depending on the service availability of said elevator car;
• a main controller for providing varied information regarding service availability of the elevator car to the sub-controllers, wherein the main controller further includes
• a state response instruction signal generating unit for generating a state response instruction signal in order to detect abnormality of the sub-controllers, and for transmitting it to the sub-controllers,
• a first timer for setting a response period from the sub-controllers responding to the state response instruction signal, and for outputting an output signal representing an expiration of the response period when it lapses,
• a counter for counting a predetermined transmission number of the state response instruction signal, and for outputting an output signal when it counts up, and
• a sub-controller abnormality determining unit for determining abnormality of the sub-controllers depending on the output signal from the timer, the output signal from the counter and the state response signal from the sub-controllers,
• and wherein each of the sub-controllers further comprises a state response signal generating unit for outputting to the main controller a response signal representing that the sub-controller is normally operated, responding to the state response instruction signal;
• and
• a serial communication line for providing a communication line between the plurality of sub-controllers and the main controller.