Benning IT 100, Operating Manual, Page: 29 / 42

Operation
5.6 Insulating resistance measurement
5225 / 04/2022 en BENNING IT 100 29
Procedure
1. Set the rotary switch of the device to switch position “LoΩ”.
2. Connect the safety measuring lines to the device [
}
page 25].
3. Only for new safety measuring lines: Briefly short-circuit the two measuring probes of the
safety measuring lines by contacting them and start the null balance by pressing the blue
key.
After successful null balance, “ZERO” is shown on the digital display. Please note that the
resistance to be compensated must not exceed 2 Ω.
4. Bring the safety measuring lines into contact with the measuring points.
5. Press and hold the “TEST” key until the measured value is shown on the digital display.
– As long as you keep the “TEST” key pressed, the measurement is active and the
displayed measured value may change.
– During an active measurement, “TEST” is shown on the digital display.
– The measured value will be displayed until a new test is started or another rotary switch
position is set.
– In case of four acoustic signals being emitted, the measurement was not successful and
the measurement has to be started again.
– Alternatively, you can also use the “LOCK” function [
}
page 21] .
6. Read the measured value on the digital display.
Please note that if the measured value is outside the measuring range, the “>” symbol will
be displayed. In this case, the displayed measured value does not correspond to the actual
value, but to the maximum value of the measuring range.
5.6 Insulating resistance measurement
Requirements
• Please observe the requirements for measuring [
}
page 24].
• Approved safety measuring lines
• Measuring ranges for insulating resistance measurement [ } page 23]
• Fuse has been tested [ } page 34]
• Measuring point must be free of voltage
WARNING
Dangerous voltage
Danger to life or serious injury is possible due to contact with high electric voltage in case of
incorrect operation. During insulating resistance measurement, dangerous testing voltages
might be present at the device. These might also be applied to the measuring circuit if safety
measuring lines are contacted.
• Do not touch the bare measuring probe tips of the safety measuring lines or the bare
contacts of the optional alligator clips, Only touch the safety measuring lines in the area
intended for your hands.