Lenovo H430 Lenovo H4 Series Hardware Maintenance Manual V2.0 - Page 7

Chapter 2. Safety information •• Wear safety glasses when you are: hammering, drilling soldering, cutting wire, attaching springs, using solvents, or working in any other conditions that might be hazardous to your eyes. •• After service, reinstall all safety shields, guards, labels, and ground wires. Replace any safety device that is worn or defective. •• Reinstall all covers correctly before returning the machine to the customer. Electrical safety CAUTION: Electrical current from power, telephone, and communication cables can be hazardous. To avoid personal injury or equipment damage, disconnect the attached power cords, telecommunication systems, networks, and modems before you open the server/workstation covers, unless instructed otherwise in the installation and configuration procedures. Observe the following rules when working on electrical equipment. Important: Use only approved tools and test equipment. Some hand tools have handles covered with a soft material that does not insulate you when working with live electrical currents. Many customers have, near their equipment, rubber floor mats that contain small conductive fibers to decrease electrostatic discharges. Do not use this type of mat to protect yourself from electrical shock. •• Find the room emergency power-off (EPO) switch, disconnecting switch, or electrical outlet. If an electrical accident occurs, you can then operate the switch or unplug the power cord quickly. •• Do not work alone under hazardous conditions or near equipment that has hazardous voltages. •• Disconnect all power before: - Performing a mechanical inspection - Working near power supplies - Removing or installing main units •• Before you start to work on the machine, unplug the power cord. If you cannot unplug it, ask the customer to power-off the wall box that supplies power to the machine and to lock the wall box in the off position. 5