Preparation For Measurement - IDEAL 61-920 Mode D'emploi

By applying the Voltage (V) to the circuit from the transformer jaw (CT1), current I is flowing
in relation to the earth resistance. R can be determined by calculation after measuring the
current with the other transformer jaw (CT2). In this case, R displayed in this meter can be
regarded as Rx because Rs can be regarded small enough against Rx.
This meter cannot support the measurement for the locations with the following earth systems.
• Single-earth that is not connected to the other earths (lighting rod, etc.)
• Earth on which a current over 2AAC is measured
• Earth with earth resistance over 1200Ω
CAUTION
10

6. Preparation for Measurement

This instrument performs self-calibration for about 3 seconds when it is turned on. ("
displayed on the LCD.) Do not clamp onto any conductor or open the jaws during this procedure.
Inaccurate measurements may occur.
(1) Check the battery voltage.
When the LCD display is blank, press the Power button
Battery voltage is sufficient when the display is legible and the "
not displayed on the LCD. Otherwise, replace the batteries to ensure accurate
measurements and proper storage of data points.
(2) Verify the correct measurement of earth resistance. Clamp the meter around the
calibration plate to ensure proper operation. If the displayed value is outside the
specified accuracy on the plate, send the instrument with the calibration plate back
to IDEAL for repair.
Resistor for operation check
1Ω loop 1Ω loop
Resistor for operation check
1Ω
10Ω
CAUTION
and turn on the meter.
Power
" mark is
Allowable range
0.93 ~ 1.07
9.75 ~ 10.25
11
" is