Mitsubishi Electronics FR-V500 Precautions for maintenance and inspection, Check items

Precautions for maintenance and inspection

6.5 Precautions for maintenance and inspection

6.5.1Precautions 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 the adverse effects of the operating environment, such as temperature, humidity, dust, dirt and vibration, changes in the parts with time, service life, and other factors.

!Precautions for maintenance and inspection

For some short time after the power is switched off, a high voltage remains in the smoothing capacitor. When accessing the inverter for inspection, switch power off, wait for more than 10 minutes, and then make sure that the voltage across the main circuit terminals P-N of the inverter is not more than 30VDC using a tester, etc.

6.5.2Check items

(1) Daily inspection

Basically, check for the following faults during operation.

1)Motor operation fault

2)Improper installation environment

3)Cooling system fault

4)Unusual vibration and noise

5)Unusual overheat and discoloration

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

(2) Cleaning

Always run the inverter in a clean status.

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 sur- face paint to peel off.

6.5.3Periodic inspection

Check the areas inaccessible during operation and requiring periodic inspection. For periodic inspection, consult us.

1)	Cooling system fault	: Clean the air filter, etc.
2)	Tightening check and retightening	: The screws and bolts may become loose due to vibration, temperature

changes, etc. Check and tighten them.

Tighten them according to the specified tightening torque. (Refer to page 11.)

3)Check the conductors and insulating materials for corrosion and damage.

4)Measure insulation resistance.

5)Check and change the cooling fan and relay.

6.5.4Insulation resistance test using megger

1)Before performing the insulation resistance test 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 m egger or buzzer.

3)For the inverter, conduct the insulation resistance test on the main circuit only as shown below and do not per- form the test on the control circuit. (Use a 500VDC megger.)

Power supply

500VDC megger

R		U	Motor
	Inverter		IM
S		V
T		W

Earth (ground) terminal

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