Electro-Tech systems 406D Operating Manual page 4

1.0 INTRODUCTION
Electrostatics is the oldest form of electrical phenomena known, but it is probably the
least understood and the hardest to control. With the advent of synthetic materials in
just about everything we wear or use, and the advancement of technology where even
the slightest over stress will destroy or damage equipment, the effects of undesirable
static charges are felt every day. The inherent non-conductivity of most synthetics,
especially under dry conditions, causes the accumulation of static charge during
processing and handling. This charge buildup, if present in an explosive atmosphere,
could cause a spark discharge resulting in explosion. If the charge buildup is present
near sensitive electronic components or equipment, it could cause product failure, or
promote the accumulation of dust or dirt, which could prove detrimental during further
processing. At the consumer level, a static charge buildup can be an annoyance, or at
worst, can prevent a product from performing as intended.
There are several ways to determine the effectiveness of static protective material. One
effective test method is the Static Decay test described in Mil Std 3010, Method 4046,
"Antistatic Properties of Materials". This method measures of the ability of a material,
when grounded, to dissipate a known charge that has been induced or applied onto the
surface of a material. A copy of the Test Method can be found in Appendix A.
Two of the most common requirements are found in the National Fire Protection
Association (NFPA) Code 99, "Standard For The Use Of Inhalation Anesthetics"
(1973), paragraph 466 ("Antistatic Accessories and Testing") and Military Specifications
Mil-PRF-81705D, "Barrier Materials, Flexible, Electrostatic Free, Heat Sealable". NFPA
99 is the test standard used for products used in the hospital operating room and for
products used in hazardous environments (referenced in NFPA 77 "Static Electricity").
Mil-PRF-81705C is the primary specification used for static protective materials for use
in the military. Fed-TM-191A, Method 5931 specifies the static decay test for static
control fabrics. The Electronics Industry Association (EIA) Standard EIA 541 and the
Electrostatic Discharge Association Standard ANSI/ESD S 541 also reference static
decay for qualifying material for use as electronics packaging. In addition, other military
standards reference Mil-PRF-81705D for qualifying specific material types.
The Model 406D Static Decay Meter is a completely integrated system for measuring
the electrostatic characteristics of materials in accordance with Method 4046. The
Model 406D is the latest version of the ETS 406 series of static decay measuring
equipment that now incorporates both manual and automatic testing modes. This
equipment is used as the test standard for qualifying material per Mil-PRF-81705D.
The Model 406D can be used as a laboratory instrument for analyzing the electrostatic
characteristics of existing materials, the effectiveness of antistatic additives and sprays,
and the development of new static-protective materials; or as a quality control
instrument for monitoring the electrostatic characteristics of production per established
specifications.
Many different electrode configurations are available which enable the user to test any
reasonable size or shape material. Standard Magnetic Electrodes are for film and fabric
samples, Clamp Electrodes are for sheet, foam and any type of sample up to one (1)
inch thick, plus optional I.C. Tube Electrodes for non-destructive testing of I.C. shipping
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