Lucent Technologies SLC-2000 Access System Central Office Terminal, Инструкция по сборке

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363-208-010
General Information
Issue 5 May 1997
1-3
Electrostatic Discharge Protection
Requirements
To reduce the possibility of ESD damage, assemblies are equipped with
grounding jacks to enable personnel to ground themselves using wrist straps
while handling circuit packs or working on an assembly. The jacks for connection
of wrist straps are located at each assembly and are labeled. When grounding
jacks are not provided, an alligator clip adapter enables connection to bay frame
ground.
All circuit packs shall be stored and transported in original factory packing
materials whenever possible. Storage in frames or approved antistatic packaging
is acceptable when factory packaging is unavailable.
Whenever a circuit pack with ICs is removed from, or inserted into, the frame or
from its container, an antistatic wrist strap must be used.
The antistatic wrist strap must be inspected once a day for damages or when it is
suspected that the wrist strap has been stressed.
Before using the antistatic wrist strap, verify with a volt-ohmmeter that
approximately 1 megohm resistance is present between the wrist strap frame
connector and the wrist harness.
The clip or plug connector of the wrist strap must be connected to a ground which
is common with the circuit pack ground. Use the equipment bay or shelf ESD
ground jack.
In an emergency, when a properly functioning wrist strap is not available at the job
site, the following “touch-ground” procedure shall be used for handling circuit
packs containing electronic components.
■
Always touch ground (exposed) metal before handling a circuit pack in
any way (i.e., inserting, removing, or storing). This must be done just
prior to touching the circuit pack. Moving around will necessitate
repeating this procedure. Note that painted surfaces are not good
ground points.
■
Handle circuit packs only by the faceplate or latch and by the top and
bottom outermost edges. Never touch the components, leads, or con-
nector pins.
■
Put the circuit pack into an antistatic bag or carton immediately upon
removing it from a frame.
A grounded person must never hand an unprotected circuit pack to a person who
is ungrounded. A static discharge from the ungrounded person through the circuit
pack to the grounded person could cause an ESD induced failure. All persons and
equipment at a work location must be at common ground potential to be static-
safe.
Do not rub or wipe circuit packs containing ICs to clean them or their gold fingers
unless both the individual and the circuit pack are the same ground potential.