Hioki IR5050 - DD Measurement (Dielectric Discharge)

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DD Measurement (Dielectric Discharge)
4.5 DD Measurement (Dielectric Discharge)
Used to diagnose a multi-layer insulator.
Since the result of this test is dependent on discharge characteristics, the internal
condition of the insulating material can be tested with little regard to surface
contamination. When the condition of the insulating material is good, the instrument
displays a DD value of less than 2.
Overview of test
The result is calculated with the following formula by performing the insulation
resistance measurement for the specied time and then using the discharge current
one minute after the measurement has ended and the capacitance of the object
under measurement.
DD (dielectric discharge)
==
Voltage at end of measurement (V)
×
Capacitance (μF)
Current 1 min. after end of measurement (nA)
Default setting: 30 min.
See: “4.6 Changing Settings for the Insulation Diagnosis Functions” (p. 70)
1
Turn the rotary switch to one of the selections between 250 V and
2505k
▲
▼
V
.
2
Press the MODE key and select the [DD] display.
Specied time
Set voltage
HIOKI IR5050A961-00