− 11 −
Note :
• When the object measured is in the live status (≥30 V AC/DC), the
display shows the voltage value together with and a warning
tone is generated. In this case, the test voltage is not output by
pressing the TEST button. To start measurement, turn the power
supply to the object measured OFF or discharge it.
• The batteries consume rapidly in measurement of resistance
lower than rated test voltage x 0.001 MΩ for a long period. It is
recommended to measure low resistances quickly in a short period.
Example) Lower than 5 MΩ when the voltage is 5000 V,
lower than 0.5 MΩ when it is 500 V.
• The maximum measurement period is 99 min. 59 seconds. The
time display blinks when this limit is exceeded.
* Principles of insulation resistance measurement: The tester
detects the current flowing through the object measured during
application of DC voltage and calculates the resistance value
with the following formula.
Current: I
Resistance value: Rx
Earth (+)
Voltage: V
Resistance value = Voltgage / Current
(Rx = V / I)
Line(-)
5-4 Discharge Function
When the insulation resistance of a capacitive object is measured, it
is charged by the test voltage. This function is provided to discharge
the high voltage remaining in the object after measurement.
1) When stopping the insulation resistance measurement, keep
the test leads connected to the object measured, and press
and hold the TEST button for more than 1 second to turn off
the power.
2) Discharging starts automatically. While the charge is discharged
from the object measured, the display shows together with
the voltage value. disappears when the discharge completes
or the charge drops to 29 V or less.