Xerox Phaser 3120 Service Manual

Also see for 3130 - Phaser B/W Laser Printer: Specifications Install guide User guide Quick reference guide

1-4PrecautionsService Manual1.3 ESD PrecautionsCertain semiconductor devices can be easily damaged by static electricity. Such components are commonlycalled “Electrostatically Sensitive (ES) Devices”, or ESDs. Examples of typical ESDs are: integrated circuits,some field effect transistors, and semiconductor “chip” components.The techniques outlined below should be followed to help reduce the incidence of component damage causedby static electricity.Caution >>Be sure no power is applied to the chassis or circuit, and observe all other safety precautions.1. Immediately before handling a semiconductor component or semiconductor-equipped assembly, drain offany electrostatic charge on your body by touching a known earth ground. Alternatively, employ a commer-cially available wrist strap device, which should be removed for your personal safety reasons prior to apply-ing power to the unit under test.2. After removing an electrical assembly equipped with ESDs, place the assembly on a conductive surface,such as aluminum or copper foil, or conductive foam, to prevent electrostatic charge buildup in the vicinityof the assembly.3. Use only a grounded tip soldering iron to solder or desolder ESDs.4. Use only an “anti-static” solder removal device. Some solder removal devices not classified as “anti-static”can generate electrical charges sufficient to damage ESDs.5. Do not use Freon-propelled chemicals. When sprayed, these can generate electrical charges sufficient todamage ESDs.6. Do not remove a replacement ESD from its protective packaging until immediately before installing it. Mostreplacement ESDs are packaged with all leads shorted together by conductive foam, aluminum foil, or acomparable conductive material.7. Immediately before removing the protective shorting material from the leads of a replacement ESD, touchthe protective material to the chassis or circuit assembly into which the device will be installed.8. Maintain continuous electrical contact between the ESD and the assembly into which it will be installed,until completely plugged or soldered into the circuit.9. Minimize bodily motions when handling unpackaged replacement ESDs. Normal motions, such as thebrushing together of clothing fabric and lifting one’s foot from a carpeted floor, can generate static electric-ity sufficient to damage an ESD.