A Primer on Electro-Static Discharge
Teledyne API Model 701 Zero Air Generator
8-4 01671H (DCN6051)
A charge can be induced onto the conductive surface and/or discharge triggered in the
presence of a charged field such as a large static charge clinging to the surface of a
nylon jacket of someone walking up to a workbench.
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.
8.4 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.
8.4.1 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 (refer to figure 12-2).
Wrist Strap
Protective Mat
Ground Point
Figure 8-2: 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.
