• Ensure correct and clean contact to UUT. A bad contact to UUT may cause the interruption
of the measurement.
• The test voltage remains present at UUT until the ISO-PRO has determined the insulation
resistance value or as long as the "Start" key (20) is pressed.
• During the measurement the symbol of the measurement unit (MΩ/GΩ) is displayed.
• If the measurement value falls below the pre-set limit value, a signal is audible after the end
of the measurement and the ""-symbol appears.
• To store the measurement result, press the "Save" key (21).
• The measurement value remains displayed until the start of a new measurement procedure
or until a different measurement range is selected.
• The UUT is automatically discharged after the measurement. During this time the symbol
of the measurement unit is blinking.
External voltage protection for insulation resistance measurement range.
If a external voltage of maximum 1200 V is connected by mistake to the insulation
measurement socket, the ISO-PRO will not be damaged.
The instrument display indicates +"UEXT". After removal of the external voltage wait for
approx. 30 seconds. Only then correct measurement results will be indicated.
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