YASKAWA FSDrive-MV1000 Series, Instructions For Use Manual

Page: 194 / 260

6.2 Inspection
194 YASKAWA ELECTRIC TOEP C710687 02B FSDrive-MV1000 Instructions
Perform out periodic inspections in the manner described below.
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Megger Check (Measurement of Insulation Resistance)
Measure Insulation Resistance of the Drive Primary Circuit
Use a 1000 V Megger insulation resistance tester.
The measured insulation resistance must be 30 M
Ω
or more.
If the input voltage detection circuit (option) is installed, disconnect the wiring to the voltage detection sensor before
measuring insulation resistance as the primary circuit is grounded at high-resistance for input voltage detection.
Measure Insulation Resistance of the Drive Secondary Circuit (Motor Side)
Use a 1000 V Megger insulation resistance tester.
The measured insulation resistance must be 2 M
Ω
or more.
The secondary circuit is grounded at high-resistance for output voltage detection. Disconnect the high-resistance resistor
for voltage detection and Power Cell output cables connected to the output terminals before measuring insulation
resistance.
Measure Insulation Resistance of the Surge Absorber
Use a 1000 V Megger insulation resistance tester.
The measured insulation resistance must be 1000 M
Ω
or more.
Note: Make sure that the surge absorber has been removed from the circuit.
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Screws, Bolts, and Connectors
WARNING! Fire Hazard. Tighten all terminal screws to the specified tightening torque. Loose electrical connections could result in
serious injury or death by fire due to overheating of electrical connections.
Loose wiring connections of the main circuit cable could cause the connections to overheat and start a fire. During
periodic inspections, be sure to retighten the screws and bolts, and to reinsert the connector securely. For the tightening
torque of the screws and bolts, refer to the following recommendations.
• M8 bolts: 8.9 N x m to 10.8 N x m
• M10 bolts: 18 N x m to 23 N x m
• M12 bolts: 31.5 N x m to 39.5 N x m
• M16 bolts: 78.5 N x m to 98 N x m
Check the following items:
• High-voltage input terminals, high-voltage output terminals
• Input voltage detection circuit (option), output voltage detection circuit
• Transformer primary terminals/primary voltage tap terminals
• Transformer secondary terminals
• Power Cell I/O terminals and fiber optic cable connector
• Power Cell screws, bolts, and connectors
• Control power supply input terminals
• Control transformer I/O terminals (option)
• Power relay I/O terminals for cooling fans
• Screws, bolts, and connectors of each control board
• Control I/O terminals
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Transformer
Check the following items:
• Check for anything abnormal in the external appearance.
• Check for discoloration indicating burn marks.
• Check for accumulated dirt and dust then remove.
If you find any, clean it away.
• Check for loose bolts in the I/O terminals and tap terminals. Retighten bolts to the recommended tightening torque.