Removal and Replacement Preliminaries
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■Nonconductive plastic bags, tubes, or boxes
■Metal tote boxes
■Electrostatic voltage levels and protective materials
Table
Table
Typical Electrostatic Voltage Levels
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| Relative Humidity | |
Event | 10% | 40% | 55% |
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Walking across carpet | 35,000 V | 15,000 V | 7,500 V |
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Walking across vinyl floor | 12,000 V | 5,000 V | 3,000 V |
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Motions of bench worker | 6,000 V | 800 V | 400 V |
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Removing DIPS from plastic tube | 2,000 V | 700 V | 400 V |
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Removing DIPS from vinyl tray | 11,500 V | 4,000 V | 2,000 V |
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Removing DIPS from Styrofoam | 14,500 V | 5,000 V | 3,500 V |
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Removing bubble pack from PCB | 26,500 V | 20,000 V | 7,000 V |
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Packing PCBs in | 21,000 V | 11,000 V | 5,000 V |
✎ A product can be degraded by as little as 700 V.
Table
Table
Static-Shielding Materials
Material | Use | Voltage Protection Level |
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Antistatic plastic | Bags | 1,500 V |
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Floor mats | 7,500 V | |
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Metallized laminate | Floor mats | 5,000 V |
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Maintenance and Service Guide |