PROTECTIVE FUNCTIONS
5.3.4 Insulation resistance test using megger
1)Before performing the insulation resistance test using a megger on the external circuit, disconnect the cables from all terminals of the inverter so that the test voltage is not applied to the inverter.
2)For the continuity test of the control circuit, use a tester (high resistance range) and do not use the megger or buzzer.
3)For the inverter, conduct the insulation resistance test on the main circuit only as shown below and do not perform the test on the control circuit. (Use a 500VDC megger.)
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Power | U |
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S<L2> | V |
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T<L3> | M |
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DC500V megger
Ground terminal
5.3.5 Dielectric strength test
Do not conduct a dielectric strength test. The inverter's main circuit uses semiconductors, which may be deteriorated if a pressure test is made.
Daily and Periodic Inspection
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| environment | dust, dirt, etc. |
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| { | { | (1) Disconnect all | (1) 5M Ω | or more. |
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| ground terminal). |
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| measure across |
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| General | screws and bolts. |
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| U, V, W <L1, L2, |
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35
