Q&A(FAQ)
Withstand Voltage and Insulation Resistance Test Instructions

Please take the following instructions into consideration in running a withstand voltage test and an insulation resistance test as an incoming inspection.

1. Voltage applying method

When running a withstand voltage test, please apply voltage gradually from 0V, or by using zero-crossing switch in order not to cause a surge voltage.
Same as the case of applying voltage, when shutting off voltage, please decrease the applied voltage gradually or by using zero-crossing switch.

2. Applied voltage

Depending on the kind of withstand voltage tester, applied voltage may be deformed or high voltage may occur in the electric circuit.
Therefore, please keep observation on the applied voltage wave pattern during the test.

3. Residual voltage

After an insulation resistance test, discharge the voltage remaining inside the Y-capacitor by resistance.

*Reference: Test circuit in COSEL

In withstand voltage isolation resistance test, L and N are shorted and +Vout and -Vout are shorted as shown in Fig.3.1 - Fig.3.3.
This test method is based on JEITA RC-9131.

Fig.3.1 Between Input and Output

Fig.3.2 Between Input and FG

Fig.3.3 Between Output and FG

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