3.3 Precautions for Maintenance and Inspection

The inverter is a static unit mainly consisting of semiconductor devices. Daily inspection must be performed to prevent any fault from occurring due to adverse influence of the operating environment, such as temperature, humidity, dust, dirt and vibration, changes in the parts with time, service life, and other factors.

3.3.1 Precautions for maintenance and inspection

For some short time after the power is switched off, a high voltage remains in the smoothing capacitor. Therefore, when more than 10 minutes have elapsed after power-off, make sure that the voltage across the main circuit terminals P-N of the inverter is 30VDC or less using a meter, etc. Then, access the inverter for inspection.

3.3.2 Check items

(1)Daily inspection

Check the following:

1)Motor operation fault

2)Improper installation environment

3)Cooling system fault

4)Unusual vibration and noise

5)Unusual overheating and discoloration

During operation, check the inverter input voltages using a meter.

(2)Cleaning

Always run the inverter in a clean state.

When cleaning the inverter, gently wipe dirty areas with a soft cloth immersed in neutral detergent or ethanol.

CAUTION

Do not use solvent, such as acetone, benzene, toluene and alcohol, as they will cause the inverter surface paint to peel off.

3.3.3 Periodic inspection

Check the areas inaccessible during operation and requiring periodic inspection.

1)Cooling system:..........Clean the air filter, etc.

2)Screws and bolts:.......These parts may become loose due to vibration, temperature changes, etc. Check that they are tightened securely and retighten as necessary.

3)Conductors and insulating materials: Check for corrosion and damage.

4)Insulation resistance: Measure.

5)Cooling fan, smoothing capacitor, relay: Check and change if necessary.

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Mitsubishi FR - S500 Precautions for Maintenance and Inspection, Precautions for maintenance and inspection, Check items