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Chapter 7
Routine Maintenance
General
This section of the manual contains routine maintenance information regarding the Valhalla
Scientific Model 4021 Digital Ohmmeter. Calibration should be performed on a regular basis to
ensure continued instrument accuracy. The recommended calibration interval is 1 year.
Required Test Equipment
Following is a list of the standard resistors and other equipment required to calibrate the Model
4021.
Precision Resistors:
10
Ω
±
0.005% Accuracy
100
Ω
±
0.005% Accuracy
1K
Ω
±
0.005% Accuracy
10K
Ω
±
0.005% Accuracy
100K
Ω
± 0.005% Accuracy
1M
Ω
± 0.005% Accuracy
Test Leads:
4-Wire Lead Set
(Valhalla Option "K" or "C")
Voltage Standard:
Voltage Calibrator capable of outputting negative 100mV, 0.03% Accuracy or better.
(Valhalla Model 2701C)
