Operation: Models 5000N, 5100 & 5110; The Analog Scale - AEMC 5100 User Manual

Megohmmeter Models 5000N/5100/5110
OPERATION: MODELS 5000N, 5100 & 5110

The Analog Scale

Before taking any measurements, verify that the pointer is zeroed
correctly (red AC scale "0"). If it is not, adjust with the mechanical
zero adjust screw.
The analog scale serves two functions:
First, it indicates the actual resistance of the insulating material under
test (black scales). The TOP scale is used for measurement on the MΩ
and GΩ ranges. The bottom half (MΩ) covers the range of 30MΩ to
30,000MΩ (3MΩ to 30,000MΩ for Model 5110), reading from left to right.
The upper half of the scale (GΩ) covers the range of 3GΩ to 3000GΩ
and reads right to left.
The center portion of the scale is used for the low insulation test range of
10kΩ to 30,000kΩ, reading from right to left.
The bottom red arc is an AC/DC voltmeter that is divided into 10 volt
increments. The voltmeter function is operable any time the PUSH-TO-
TEST button is out. The voltmeter detects the presence of voltage on the
equipment to be tested. (If voltage is detected, do not proceed with
the insulation test).
The voltmeter function also indicates if, after completing insulation
testing, the sample under test has stored a dangerous capacitive charge.
The instrument discharges this capacitance internally and the needle will
drop accordingly. Disconnect the meter when the sample is discharged.
Warning:
Electrical equipment and cables may have sufficient capacitance to store
a dangerous charge from the instrument test current. For proper
discharge to occur the PUSH-TO-TEST button must be in the OFF
position with the sample connected between the EARTH and LINE
terminals.
On prolonged tests, the PUSH-TO-TEST button may be locked in the ON
position; care should be taken in this mode that no damage is done if the
instrument is left unattended.
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