Teledyne T703, T703U 10.4. BASIC PRINCIPLES OF STATIC CONTROL

A Primer on lectro-Static Discharge Teledyne API T703/T703U Calibrator Operation Manual

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10.4. 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.

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.

Wrist Str

Protective Mat

Ground Point

Figure 10-2: 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 instrument. 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.

 Always store sensitive components and assemblies in anti-ESD storage bags

or bins: Even when you are not working on them, store all devices and assemblies

in a closed anti-Static bag or bin. This will prevent induced charges from building

up on the device or assembly and nearby static fields from discharging through it.

 Use metallic anti-ESD bags for storing and shipping ESD sensitive

components and assemblies rather than pink-poly bags. The famous, pink-poly

bags are made of a plastic that is impregnated with a liquid (similar to liquid laundry

detergent) which very slowly sweats onto the surface of the plastic creating a

slightly conductive layer over the surface of the bag.

While this layer may equalizes any charges that occur across the whole bag, it does not

prevent the build up of static charges. If laying on a conductive, grounded surface, these

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