HP Xw9400 HP xw9400 Workstation - Service and Technical Reference Guide - Page 62

Generating static The following table shows that different activities generate different amounts of static electricity. Static electricity increases as humidity decreases. Table 5-1 Static electricity Relative Humidity Event 5% 4% 1% Walking across carpet 7,500 V Walking across vinyl floor 3,000 V Motions of bench worker 400 V Removing bubble pack from PCB 7,000 V Packing PCBs in foam-lined box 5,000 V 15,000 V 5,000 V 800 V 20,000 V 11,000 V 35,000 V 12,000 V 6,000 V 26,500 V 21,000 V CAUTION: 700 volts can degrade a product. Preventing electrostatic damage to equipment Many electronic components are sensitive to ESD. Circuitry design and structure determine the degree of sensitivity. The following packaging and grounding precautions are necessary to prevent damage to electric components and accessories. ● Transport products in static-safe containers, such as tubes, bags, or boxes, to avoid hand contact. ● Protect all electrostatic parts and assemblies with conductive or approved containers or packaging. ● Keep electrostatic-sensitive parts in their containers until they arrive at static-free stations. ● Place items on a grounded surface before removing them from their containers. ● When handling or touching a sensitive component or assembly, ground yourself by touching the chassis. ● Avoid contact with pins, leads, or circuitry. ● Place reusable electrostatic-sensitive parts from assemblies in protective packaging or conductive foam. 52 Chapter 5 Removal and replacement procedures ENWW