Removing DIPs* from vinyl tray
Removing DIPs* from Styrofoam
Removing bubble pack from PCB
Packing PCBs in foam-lined box
2,000 V
3,500 V
7,000 V
5,000 V
4,000 V
5,000 V
20,000 V
11,000 V
11,500 V
14,500 V
26,500 V
21,000 V
*These are then multi-packaged inside plastic tubes, trays, or Styrofoam.
NOTE: 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.
●
To avoid hand contact, transport products in static-safe containers such as tubes, bags, or
boxes.
●
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 container.
●
Always be properly grounded when touching a sensitive component or assembly.
●
Avoid contact with pins, leads, or circuitry.
●
Place reusable electrostatic-sensitive parts from assemblies in protective packaging or
conductive foam.
Personal Grounding Methods and Equipment
Use the following equipment to prevent static electricity damage to equipment:
●
Wrist straps are flexible straps with a maximum of one-megohm ± 10% resistance in the ground
cords. To provide proper ground, a strap must be worn snug against bare skin. The ground cord
must be connected and fit snugly into the banana plug connector on the grounding mat or
workstation.
●
Heel straps/Toe straps/Boot straps can be used at standing workstations and are compatible
with most types of shoes or boots. On conductive floors or dissipative floor mats, use them on
both feet with a maximum of one-megohm ± 10% resistance between the operator and ground.
Static Shielding Protection Levels
Method Voltage
Antistatic plastic
Carbon-loaded plastic
Metallized laminate
1,500
7,500
15,000
28 Chapter 5 Identifying the Chassis, Routine Care, and Disassembly Preparation