Use this formula to determine the value of an external shunt resistor
(meter impedance >10 M
Ω
):
Where:
Rs = Shunt resistance in M
Ω
Rm = Voltmeter input impedance in
ΜΩ
(>10 M
Ω
)
Example: If Rm = 20 M
Ω
,
Use this formula to calculate a correction factor (meter impedance
<10 M
Ω
):
Where:
Cf = Correction factor (multiplier for meter reading)
Rm = Voltmeter input impedance in M
Ω
Example: If Rm = 1 M
Ω
,
A meter reading of 0.526 volts represents an input of:
0.526 x 1.901 = 1 or 1 kV
Circuit Loading
The probe represents a load to the circuit:
•
1000 M
Ω
, or 1
μ
A/1 kV, for 80K-40
•
75 M
Ω,
or 13
μ
A/1 kV, for 80K-6
Maintenance
The probe has no user-serviceable parts.
Use a soft cloth dampened with distilled water to clean the probe. Never
use solvents of abrasive cleaners. Make sure the probes are dry before
use.
Performance Test
Verify the accuracy of the probe with a voltage source measurement:
•
25 kV dc ±0.25 % for 80K-40
•
5 kV dc ±0.25 % for 80K-6
When used with a compatible dc voltmeter, the probe should measure the
source with ±1 % accuracy. No calibration adjustments are available on
the probe.
Specifications
Voltage Range
80K-40:
0 kV to
±
40 kV dc or peak ac, 28 kV rms ac
80K-6:
0 kV to
±
6 kV dc or peak ac, 4.24 kV rms ac
Input Resistance
80K-40:
1000 M
Ω
80K-6:
75 M
Ω
nominal
Division Ratio:
1000:1 (1000 x attenuation)
Rs
Rm x 10
Rm 10
=
−
Rs
20 10
×
20 10
–
-------------------
200
10
----------
20
M
Ω
=
=
=
Cf
1.11 + Rm
1.11 x Rm
=
Cf
1.11 + 1
1.11 x 1
=
2.11
1.11
= 1.901
=
