A KUKA controller in failsafe state indicates a critical error or safety violation that has prevented the robot from operating normally. The robot will be immobilized, and all safety functions will be activated.

When a KUKA controller enters a "failsafe state," it typically means that the system has detected a critical issue that could compromise safety or the proper functioning of the robot. In this state, the robot is designed to stop all motion and shut down certain systems to prevent damage or injury.

Possible Causes of the Failsafe State:

1. Safety Circuit Issue:

   • The most common cause is a problem in the robot's safety circuit, such as a triggered emergency stop, a tripped safety relay, or a fault in the safety PLC.

2. Hardware Fault:

   • A failure in one of the robot’s key components, such as the servo drives, power supply, or sensors, can trigger the failsafe state.

3. Communication Failure:

   • Loss of communication between the robot controller and the safety devices or between the controller and the teach pendant (SmartPad) can cause the robot to enter a failsafe state.

4. Configuration or Software Error:

   • Corrupted or incorrect configuration settings, or a software bug, can cause the controller to fail to operate normally and enter a failsafe state.

5. Overheating or Power Issues:

   • Overheating of critical components, or unstable power supply to the controller, could trigger a failsafe condition to protect the hardware.

6. External Interference:

   • Electrical noise or interference from nearby equipment could disrupt the control signals, leading the robot to enter a failsafe state.

Troubleshooting Steps:

1. Check Safety Devices:

   • Inspect all safety devices connected to the robot, including emergency stop buttons, light curtains, safety relays, and safety PLCs. Ensure that none of these devices have been triggered or are malfunctioning.

2. Reset Safety Circuits:

   • Attempt to reset the safety circuits by releasing any triggered emergency stops and ensuring all safety devices are in their normal operational state. Then, try resetting the robot controller.

3. Inspect Hardware Components:

   • Check the robot’s hardware, including servo drives, power supplies, and any connected sensors, for signs of failure or damage. Look for overheating indicators or any other warning signs.

4. Verify Connections:

   • Ensure that all communication cables between the controller, teach pendant, and safety devices are securely connected and free from damage. Loose or damaged cables can cause communication failures.

5. Review Configuration and Software:

   • Check the robot’s configuration settings using KUKA WorkVisual or the SmartPad. Look for any discrepancies or errors in the configuration files. Revert to a known good configuration if necessary.

6. Check for Overheating or Power Issues:

   • Ensure that the robot’s controller is operating within the recommended temperature range and that the power supply is stable and within specifications. If overheating is detected, improve ventilation or reduce the robot’s workload.

7. Reset the Controller:

   • Power cycle the robot controller. This can sometimes clear temporary faults and reset the system from the failsafe state.