IBM 2179 Hardware Maintenance Manual

Also see for 2179: User guide Technical information manual User guide Podręcznik użytkownika

Contents

Observe the following rules when working on electrical equipment.v Find the room emergency power-off (EPO) switch, disconnecting switch, orelectrical outlet. If an electrical accident occurs, you can then operate the switchor unplug the power cord quickly.v Do not work alone under hazardous conditions or near equipment that hashazardous voltages.v Disconnect all power before:– Performing a mechanical inspection– Working near power supplies– Removing or installing main unitsv Before you start to work on the machine, unplug the power cord. If you cannotunplug it, ask the customer to power-off the wall box that supplies power to themachine and to lock the wall box in the off position.v If you need to work on a machine that has exposed electrical circuits, observe thefollowing precautions:– Ensure that another person, familiar with the power-off controls, is near you.Remember:Another person must be there to switch off the power, ifnecessary.– Use only one hand when working with powered-on electrical equipment;keep the other hand in your pocket or behind your back.Remember:There must be a complete circuit to cause electrical shock. Byobserving the above rule, you may prevent a current from passing throughyour body.– When using testers, set the controls correctly and use the approved probeleads and accessories for that tester.– Stand on suitable rubber mats (obtained locally, if necessary) to insulate youfrom grounds such as metal floor strips and machine frames.Observe the special safety precautions when you work with very high voltages;these instructions are in the safety sections of maintenance information. Useextreme care when measuring high voltages.v Regularly inspect and maintain your electrical hand tools for safe operationalcondition.v Do not use worn or broken tools and testers.v Never assume that power has been disconnected from a circuit. First, check that ithas been powered-off.v Always look carefully for possible hazards in your work area. Examples of thesehazards are moist floors, nongrounded power extension cables, power surges,and missing safety grounds.v Do not touch live electrical circuits with the reflective surface of a plastic dentalmirror. The surface is conductive; such touching can cause personal injury andmachine damage.v Do not service the following parts (or similar units) with the power on when theyare removed from their normal operating places in a machine. This practiceensures correct grounding of the units.)– Power supply units– Pumps– Blowers and fans– Motor generatorsv If an electrical accident occurs:– Use caution; do not become a victim yourself.– Switch off power.– Send another person to get medical aid.Chapter 8. Related service information 103