TB-6520
Page 5 of 7
Per ANSI/ESD 7.1 (Floor) Report:
• RTG all values in ohms for resistance to ground
• RTT all values in ohms for point-to-point resistance
• Voltage level
• Test date
• Temperature
• Relative humidity
• Test equipment used
Summarize test data by reporting minimum, maximum,
median, and mean values obtained. Include a diagram
showing approximate electrode positions and ground
connections used.
Recommended Frequency of Compliance
Verification Periodic Checks of ESD Control
Items
Per ESD TR53 Compliance Verification of ESD Protective
Equipment and Materials ANNEX A “Each user will need
to develop their own set of test frequencies based on the
critical nature of those ESD sensitive items handled and
the risk of failure for the ESD protective equipment and
materials.
Note: “The frequency of periodic testing is normally
specified in corporate operating procedures. …The
frequency of testing is driven by the amount of risk
exposure that can occur between tests. For, example, what
is the quantity of product handled between test periods?”
(See ESD Handbook ESD TR20.20) However, a common
guide would be:
•
Worksurface
- at least quarterly (see ESD TR20.20
section 5.3.1.13 Periodic verification testing)
•
Footwear
- “Incoming inspection on a lot sampling basis
should be performed for all static control footwear.” (see
TR 20.20 section 5.3.3.4 Testing)
•
Floor
- (See ESD TR20.20 section 5.3.4.5 Performance
Monitoring) Test methods, standards, and specifications.
“Typically, once qualified, floors may use simple
resistance checks to ensure the flooring does not change.
The frequency of testing is also a consideration. Some
materials, such as floor finishes, may require more
frequent testing because of their lack of permanency.”
[ESD TR20.20 section 5.3.4.15 Test Methods,
Standardsm and Specifications
•
Seating
- “The recommended electrical resistance range
for seating is less than 1 x 10E9 ohms as tested in
accordance with ANSI/ESD STM2.1. This value should
be during acceptance testing, installation and periodically
thereafter.” (see ESD TR20.20 section 5.3.5.3 Testing)
•
Garments
- “To maintain process control, it is imperative
that the garment be tested per ANSI/ESD STM 2.1. The
point to point and sleeve to sleeve resistance test should
be made.” (see ESD TR20.20 section 5.3.13.3.1.8
Periodic Testing)
Surface Resistivity
Theoretically Resistivity is 10 times greater than Resistance,
i.e. a material that measures 10E7 ohms RTT, Surface
Resistivity should measure 10E8 ohms/square.*
Ref: ANSI/ESD S11.11 section 12.0 Conversion to
Resistivity states, “When it is appropriate to convert a
resistance obtained by this test method to an equivalent
resistivity in ohms per square, multiply the resistance
measurements obtained by this method by 10. The
conversion factor of 10 is derived from the geometry of the
electrode assembly.”
No conversion is required with the Surface Resistance Test
Kit. The Meter incorporates provision to install optional
Resis tivity Attachment which has parallel electrodes
on bottom of the unit to make direct surface resistivity
measurements. These parallel electrodes allow for
measurement of resistivity or when quick testing without the
use of 5 pound electrodes is desired.
*Note: Per ESD Association the proper unit of measurement
of resistivity is ohms or even though. ANSI/ESD S11.11
uses ohms/square.
Battery Life:
Approximately 1,500 measurements
Resistivity Electrodes:
Two parallel conductive silicone
rubber electrodes (optional item)
External Electrodes:
Two 5-pound (±2 oz) electrodes, 2.5"
in diameter, complies with ANSI/ESD S4.1
Display:
One 3.5 digit .500” Liquid Crystal Display (LCD)
Display and seventeen Light Emitting Diodes (LED’s)
illuminate exponent numbers and the function being
performed.
*
Accuracy:
Resistance measurements within ±10% (E11
& greater ±20%), complies with ANSI/ESD S4.1. Open
circuit voltages of 10 volts ± 5% and 100 volts ± 5% half the
accuracy required of ANSI/ESD S4.1
Meter Weight:
15.5 oz.
Dimensions:
8"L x 4.3"W x 1.6"H
Test Switch:
Press the red test button for 15-20 second
electrification period. Meter will immediately display surface
resistance exponent via LED. LCD will display temperature
(both Fahrenheit & Celsius), then relative humidity, and
after taking numerous readings and making numerous
calculations display surface resistance mantissa.
Note: Reporting test results, you may want to record the
resistance, humidity, temperature, and test voltage.
Maintenance
Your Surface Resistance Test Kit will require little
maintenance, and there are no user serviceable parts. If
your Meter requires service beyond cleaning the Electrodes
or replacing the batteries, please contact the factory.
This product utilizes a high frequency switching circuit
to step up the 3 volts from the batteries to the 100 volt
test level. Some users are able to discern a slight hum
or buzzing. This is perfectly normal and should not be
considered a flaw or defect.
© 2010 DESCO INDUSTRIES INC.
Employee Owned
EMIT
- 3651 Walnut Avenue, Chino, CA 91710 • (909) 664-9980 • Fax (909) 627-7449 • Website: