AEMC 1000N - Voltage Measurements (Safety Check)

Megohmmeter Model 1000N/1100N
- 14 -
When the guard terminal is connected at “B”, the instrument measures
the current “I” and not the surface leakage current “i
1
”, which is not
included in the measurement. See Figure 5. This type of measurement
will give the true value of
the resistance “Rx”,
providing the “Ry” and
“Rz” are not too low.
Figure 5
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Insulation resistance tests are to be carried out on non-energized circuits
only. Voltage measurements are made as a safety precaution. If any
voltage is present do not proceed with insulation resistance testing. This
instrument can measure both AC or DC voltages. For voltage
measurements, proceed as follows:
•
The PUSH-TO-TEST button should be in the OFF position.
•
Connect the instrument with the voltage leads connected between the
Line (-) and Earth (+) terminals on the unit.
•
Read the voltage directly on the voltage scale.
+ EARTH
- LINE
MEGOHMMETER
Figure 6
AC
B
Ry
Rz
Rx
i
1
i
To EARTH
Terminal
To LINE
Terminal
To Guard
Terminal