Which of these is NOT a safety rule to follow with robots?

• A. Don't put your fingers or hands inside any device that has a moving operation
• B. Use appropriate tools
• C. Use extreme caution when working on a mechanical device
• D. Make sure power is turned on before opening the case

Answer: (D)

De-energize before opening the robot enclosure to prevent injuries from unexpected motion and electrical energy. If power remains on, a motor or actuator could start moving, and capacitors or other stored energy can cause shocks or gear-pinching injuries while you’re inside. The safe approach is to switch off the system, disconnect power, apply lockout-tagout if available, verify there’s no residual energy, and then open the case. The other practices—keeping fingers away from moving parts, using appropriate tools, and approaching mechanical work with caution—are all solid safety habits. So turning the power on before opening the case is not a safety rule.