When a presence sensing device stops the motion of a robot, it can be reset automatically by the PLC instead of a deliberate reset by the operator.

When a presence sensing device stops the motion of a robot, it can be reset automatically by the PLC instead of a deliberate reset by the operator.

• A. True
• B. Depends on maintenance schedule
• C. Only if a fault occurs
• D. False

Answer: (D)

A deliberate reset is required after a presence sensing device stops a robot. When such a device detects a hazard, it stops motion to protect people. Re-enabling motion should not happen automatically because that could hide a dangerous condition or an operator still in the danger zone. The safety system is designed so the operator consciously acknowledges the stop, ensures the area is clear, and then performs a reset or rearm sequence before the robot can restart. That’s why the statement is false: automatic reset by the PLC is not the expected or safe behavior.

A deliberate reset is required after a presence sensing device stops a robot. When such a device detects a hazard, it stops motion to protect people. Re-enabling motion should not happen automatically because that could hide a dangerous condition or an operator still in the danger zone. The safety system is designed so the operator consciously acknowledges the stop, ensures the area is clear, and then performs a reset or rearm sequence before the robot can restart. That’s why the statement is false: automatic reset by the PLC is not the expected or safe behavior.