PS-2111
Page 5 of 7
• Worksurface - at least quarterly (see
TR 20.20 paragraph 5.3.1.13 Periodic
Tests)
• Footwear - "Incoming inspection on a
lot sampling basis should be
performed for all static control
footwear." (see TR 20.20 paragraph
5.3.3.4 Testing)
• Floor - "The types of monitoring and
type of equipment are considerations.
In some cases, a simple electrical
resistance test with a megohmmeter
may suffice. In others, a static charge
generation test may be required." (see
TR 20.20 paragraph 5.3.4.13
Performance Monitoring)
• Seating - "The recommended
electrical resistance range for seating
is less than 1 x 10E9 ohms as tested
in accordance with ESD STM 12.1.
This value should be during
acceptance testing, installation and
periodically thereafter." (see TR
20.20 paragraph 5.3.5.3 Testing)
• Garments - "To maintain process
control, it is imperative that the
garment be tested per ESD STM 2.1.
The point to point and sleeve to
sleeve resistance test should be
made." (see TR 20.20 paragraph
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: ESD S11.11 paragraph 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
Resistivity 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: Currently, there is discussion
within the ESD Association if the
proper unit of measurement of
resistivity is ohms or ohms/square.
S11.11-1993 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) weighted electrodes, 2.5" in
diameter, complies with 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 function being performed.
*
Accuracy:
Resistance measurements
within ±10% (E12 and greater ±20%)
complies with ESD-S4.1. Open circuit
voltages of 10 volts ±5% and 100 volts
±5% exceeds requirements of 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 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.
Calibration*
The Surface Resistance Test Kit is
calibrated to NIST traceable standards.
Most users require calibration annually.
Please call our Customer Service
Department at 508-485-7390 for details.
In-house calibration can be performed
by using 1% resistors in each of the
meter ranges. Simply attach the resistors
to the enclosed cords using grounding
clips and recording the meter display.
Keep the cords separated. Should
adjustment be necessary, it is
recommended that the unit be returned
to the factory as access to internal
adjustments requires special equipment
and test cables.
EQUIPMENT:
• Digital Multimeter - accurate to
1.25% @ 10VDC and 100VDC
• Fixed Decade Box value 10E3 -
10E12 - accurate to ±2.5%, except at
10E11 and 10E12 (±5%)
• Thermometer - accurate to ±1°F
• Humidity meter - accurate to 2%
• Test leads
• 99% Isopropyl alcohol and cleaning
wipes
SET UP:
A .Test Area
- Area needs to be free of
any high voltage transformer or power
supply. Not under any type of
fluorescent lighting or high power
lighting.
B. Worksurface
- needs to be covered
with conductive mat at 1.0 x 10E3 or
less, connected to earth ground.
C. Technician
- needs to be grounded
with zero ohms resistor to earth ground.
D. Decade Box
- needs to be grounded
to earth ground.
*Accuracy is measured after
normalizing the instrument at 70-80 °F
and 30-50% RH for a minimum of 4
hours.
© 2007 DESCO INDUSTRIES INC.
Employee Owned
