2-15
Figure 2-6.—ESD wrist strap.
2.
Equipment technical manuals and packaging material should be checked for ESD warnings and
instructions.
3.
Prior to opening an electrostatic unit package of an ESDS device or assembly, clip the free end of
the grounded test lead to the package. This will cause any static electricity that may have built up
on the package to discharge. The other end remains connected to the equipment frame or other
ESD ground. Keep the unit package grounded until the replacement device or assembly is placed
in the unit package.
4.
Minimize handling of ESDS devices and assemblies. Keep replacement devices or assemblies,
with their connector-shorting bars, clips, and so forth, intact in their electrostatic-free packages
until needed. Place removed repairable ESDS devices or assemblies, with their connector shorting
bars or clips installed, in electrostatic-free packages as soon as they are removed from the
equipment. ESDS devices or assemblies should be transported and stored only in protective
packaging.
5.
Always avoid unnecessary physical movement, such as scuffing the feet, when handling ESDS
devices or assemblies. Such movement will generate additional charges of static electricity.
6.
When removing or replacing an ESDS device or assembly in the equipment, hold the device or
assembly through the electrostatic-free wrap if possible. Otherwise, pick up the device or
assembly by its body only. DO NOT TOUCH component leads, connector pins, or any other
electrical connections or paths on boards, even though they are covered by conformal coating.
7.
Do not permit ESDS devices or assemblies to come in contact with clothing or other ungrounded
materials that could have an electrostatic charge. The charges on a nonconducting material are not
equal. A plastic storage bag may have a -10,000 volt potential one-half inch from a +15,000 volt
potential, with many other such charges all over the bag. Placing a circuit card inside the bag
allows the charges to equalize through the pcb conductive paths and components, thereby causing
failures. Do not hand an ESDS device or assembly to another person until the device or assembly
is protectively packaged.
8.
When moving an ESDS device or assembly, always touch (with your bare skin) the surface on
which it rests for at least 1 second before picking it up. Before placing it on any surface, touch the
