Robot system provided with a plurality of controllers which operate a plurality of industrial robots

A robot system comprising:

• a plurality of robot controllers assigned, respectively, to a plurality of industrial robots,
• the robot controllers including a master controller assigned to one of the industrial robots, and one or more slave controllers assigned to a remaining one or more of the industrial robots,
• the master controller including a first safety monitoring unit, a second safety monitoring unit, and a contactor relay configured to stop operations of the one of the industrial robots to which the master controller is assigned, and
• each of the one or more slave controllers including a first safety monitoring unit and a contactor relay configured to stop operations of the one or more industrial robots to which a corresponding one of the slave controllers is assigned;
• an operating switch configured to be manually operated to perform an emergency stop operation of the industrial robots, the operating switch being arranged outside each one of the plurality of robot controllers and connected to the second safety monitoring unit of the master controller via a first connection cable, such that an emergency manual operation at the operating switch transmits a safety input signal between the operating switch and the second safety monitoring of the master controller;
• and
• a second connection cable, wherein:
• the first safety monitoring units are configured to perform an emergency stop operation based on whether the safety input signal transmitted through the operating switch is inputted,
• the second safety monitoring unit of the master controller is configured to perform the emergency stop operation and output an enable signal based on whether the safety signal transmitted through the operating switch is inputted,
• the master controller includes a wiring path wiring an input path of the safety input signal transmitted through the operating switch and an output path of the enable signal outputted from the second safety monitoring unit, such that the input path and the output path are connected serially to the one or more slave controllers via the second connection cable outside the master controller;
• and
• each of the slave controllers includes a connection path connecting, via the second connection cable, the first safety monitoring unit of the respective slave controller to the input path of the safety input signal and connecting the contactor relay to the output path of the enable signal.