Removal and replacement procedures

Workstation guidelines

Follow these workstation grounding guidelines:

Cover the workstation with approved static-shielding material.

Use a wrist strap connected to a properly grounded work surface, and use properly grounded tools and equipment.

Use conductive field service tools, such as cutters, screwdrivers, and vacuums.

When fixtures must directly contact dissipative surfaces, use fixtures made only of static-safe materials.

Keep the work area free of nonconductive materials, such as ordinary plastic assembly aids and Styrofoam.

Handle ESD-sensitive components, parts, and assemblies by the case or PCM laminate. Handle these items only at static-free workstations.

Avoid contact with pins, leads, or circuitry.

Turn off power and input signals before inserting or removing connectors or test equipment.

Equipment guidelines

Grounding equipment must include either a wrist strap or a foot strap at a grounded workstation.

When seated, wear a wrist strap connected to a grounded system. Wrist straps are flexible straps with a minimum of one megohm ±10% resistance in the ground cords. To provide proper ground, wear a strap snugly against the skin at all times. On grounded mats with banana-plug connectors, use alligator clips to connect a wrist strap.

When standing, use foot straps and a grounded floor mat. Foot straps (heel, toe, or 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 foot straps on both feet with a minimum of one megohm resistance between the operator and ground. To be effective, the conductive strips must be worn in contact with the skin.

The following grounding equipment is recommended to prevent electrostatic damage:

Antistatic tape

Antistatic smocks, aprons, and sleeve protectors

Conductive bins and other assembly or soldering aids

Nonconductive foam

Conductive tabletop workstations with ground cords of one megohm resistance

Static-dissipative tables or floor mats with hard ties to the ground

Field service kits

Static awareness labels

Material-handling packages

Nonconductive plastic bags, tubes, or boxes

Metal tote boxes

Electrostatic voltage levels and protective materials

The following table lists the shielding protection provided by antistatic bags and floor mats.

Material

Use

Voltage protection level

 

 

 

Antistatic plastic

Bags

1,500 V

 

 

 

Carbon-loaded plastic

Floor mats

7,500 V

 

 

 

Metallized laminate

Floor mats

5,000 V

 

 

 

4–4

Maintenance and Service Guide

Page 49
Image 49
HP 4311S manual Workstation guidelines, Material Use Voltage protection level