Teledyne T101, Operation Manual, Page: 286 / 375

A Primer on Electro-Static Discharge Teledyne ML - T101 Operation Manual
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• As long as my analyzer is properly installed, it is safe from
damage caused by static discharges: It is true that when properly
installed the chassis ground of your analyzer is tied to earth ground and
its electronic components are prevented from building static electric
charges themselves. This does not prevent discharges from static fields
built up on other things, like you and your clothing, from discharging
through the instrument and damaging it.
11.4. BASIC PRINCIPLES OF STATIC CONTROL
It is impossible to stop the creation of instantaneous static electric charges. It is not,
however difficult to prevent those charges from building to dangerous levels or prevent
damage due to electro-static discharge from occurring.
11.4.1. GENERAL RULES
Only handle or work on all electronic assemblies at a properly set up ESD station.
Setting up an ESD safe workstation need not be complicated. A protective mat properly
tied to ground and a wrist strap are all that is needed to create a basic anti-ESD
workstation (see figure 11-2).
Wrist Strap
Protective Mat
Ground Point
Figure 11-2. Basic anti-ESD Work Station
For technicians that work in the field, special lightweight and portable anti-ESD kits are
available from most suppliers of ESD protection gear. These include everything needed
to create a temporary anti-ESD work area anywhere.
• Always wear an Anti-ESD wrist strap when working on the
electronic assemblies of your analyzer. An anti-ESD wrist strap
keeps the person wearing it at or near the same potential as other
grounded objects in the work area and allows static charges to dissipate
before they can build to dangerous levels. Anti-ESD wrist straps
terminated with alligator clips are available for use in work areas where
there is no available grounded plug.
Also, anti-ESD wrist straps include a current limiting resistor (usually around one meg-
ohm) that protects you should you accidentally short yourself to the instrument’s power
supply.
•
Simply touching a grounded piece of metal is insufficient. While
this may temporarily bleed off static charges present at the time, once
you stop touching the grounded metal new static charges will
immediately begin to re-build. In some conditions, a charge large
enough to damage a component can rebuild in just a few seconds.