PRF-911 Concentric Ring
15
4. To Measure the Material under test
a. Place the specimen to be tested on the insulated PTB-920 test bed with
the surface to be tested facing UP.
b. Remove the protective cap covering the PRF-911 fixture electrodes and
position the fixture on the test material in the approximate center of the
test bed.
c. Place the five pound PROSTAT NFPA electrode directly on top of the
PRF-911 fixture housing. Note the center electrode spring compression
and contact of the outer electrode ring with the material under test.
OPERATIONAL NOTE
The electrode assembly weighs approximately 28
ounces. The center electrode spring counters the
fixture weight with approximately 30 ounces when
fullyextended. When the five pound NFPA electrode
is positioned on the fixture housing, both the outer ring
and the center electrodes have approximately five
pounds total pressure across both surfaces.
d. When operating PRS-801 or PRS-812 Resistance Instruments in Automatic or
Automatic/Manual, simply press the GREEN TEST button to initiate the
measurement sequence.
The initial test voltage will be less than 10 volts (<10V), then increase based on
the material under test resistance range.
Proper test voltage protocol for resistance measurements of ESD Control
materials follows:
Resistance Range (
Ω
)
Test Voltage (V)
Remarks
< 1.0 x 10
4
<
10V
Voltage is variable.
Electrification 2-5 sec.
1.0 x 10
4 to
< 1.0 x 10
6
10V
Constant Voltage
Preferred. Electrification
2-5 sec.
> 1.0 x 10
6
100V
Constant Voltage
Preferred. Electrification
based on system
characteristics
Summary of Contents for PRF-911
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