Hioki IR4055, Instruction Manual

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Insulation Resistance Measurement
3.5 Insulation Resistance Measurement
The instrument is used to measure the insulation resistance to
determine the insulation performance of circuits and equipment.
Before starting a measurement, the voltage to be applied to the
measuring object needs to be selected.
WARNING
Observe the following to avoid electric shock, short
circuit, or damage to the instrument.
• Do not attempt to measure insulation resistance
on alive conductor. Doing so could damage the
instrument or cause an accident that might result
in injury or death. Always turn off power to the
measurement target before starting.
• When measuring insulation resistance, dangerous
voltage is applied to the measurement terminals. To
avoid electric shock, do not touch the test leads.
• Do not touch the measuring object immediately after
measurement. Doing so may cause electric shock
due to a highly charged voltage.
• Discharge the measuring object with the discharge
function of the instrument after a measurement. (p. 37)
• Insulation resistance is the ratio of applied voltage to leakage current.
Displayed value may not stabilize depending on the measuring object,
but it is not a failure of the instrument.
• Press the MEASURE key fully down until a live circuit indicator lights up.
If the button is not pressed down fully, a proper measurement cannot be
made.
• After use, turn off the rotary switch.
• Disconnection of any equipment having a lower withstanding voltage than
the test voltage, or equipment or parts having an unknown withstanding
voltage connected to the circuit to be measured is recommended.