Prostat PRF-911, Operation Manual

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PRF-911 Concentric Ring
19
OPERATIONAL WARNING
TO AVOID PERSONNEL SHOCK, DO NOT TOUCH
THE MATERIAL UNDER TEST, THE PRF-911
CONCENTRIC FIXTURE OR TEST BED DURING
ANY MEASUREMENT CYCLE.
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
(1) If the indicated measurement on the PRS-801 or PRS-812 Resistance
Instrument is less than 1.0x10
6
Ohms, record the indicated measurement in
Ohms after approximately 2 to 5 seconds of electrification.
(2) If the indicated measurement on the PRS-801 or PRS-812 Resistance
Instrument is greater than 1.0x10
6
Ohms:
(a) Select 100 Volts on the test instrument if using PRS-801 or PRS-812
Resistance Instruments. They will automatically shift to 100 Volts.
(b) After instrument’s electrification record the indicated measurement in
Ohms.
5. To calculate Volume Resistivity in Ohms-cm use the following formula.
Volume
Resistivity = 6.9 cm
2
x R
I
Ohm
in Ohm-cm t cm
where,
6.9 cm
2
is the AREA of the center electrode's (D
1
) contact surface with
the material
t = The thickness of the material in centimeters (cm)
R
I
= The Resistance as indicated on the PRS-801 or PRS-812 or the
Resistance Instrument of choice in ohms.