IBM ThinkPad 340 Series Hardware Maintenance Manual

Also see for 360: Specifications Hardware Maintenance Manual Operating guide User guide Manual

Electrical SafetyObserve the following rules when working on electricalequipment.ImportantUse only approved tools and test equipment. Somehand tools have handles covered with a soft materialthat does not insulate you when working with liveelectrical currents.Many customers have, near their equipment, rubberfloor mats that contain small conductive fibers todecrease electrostatic discharges. Do not use thistype of mat to protect yourself from electrical shock. Find the room emergency power-off (EPO) switch,disconnecting switch, or electrical outlet. If anelectrical accident occurs, you can then operate theswitch or unplug the power cord quickly. Do not work alone under hazardous conditions ornear 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 thepower cord. If you cannot unplug it, ask the customerto power-off the wall box that supplies power to themachine and to lock the wall box in the off position. If you need to work on a machine that hasexposedelectrical circuits, observe the following precautions:– Ensure that another person, familiar with thepower-off controls, is near you.Remember: Another person must be there toswitch off the power, if necessary.– Use only one hand when working withpowered-on electrical equipment; keep the otherhand in your pocket or behind your back.Remember: There must be a complete circuit tocause electrical shock. By observing the aboverule, you may prevent a current from passingthrough your body.– When using testers, set the controls correctlyand use the approved probe leads andaccessories for that tester.– Stand on suitable rubber mats (obtained locally,if necessary) to insulate you from grounds suchas metal floor strips and machine frames.Observe the special safety precautions when youwork with very high voltages; these instructions are inthe safety sections of maintenance information. Useextreme care when measuring high voltages.Introduction 15