Mitsumi electronic 55K Welding System User Manual


 
5.3 Precautions for Maintenance and Inspection
PROTECTIVE FUNCTIONS
176
5.3 Precautions for Maintenance and Inspection
The transistorized 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 by the operating environment, such
as temperature, humidity, dust, dirt and vibration, changes in the parts with time, service life, and other
factors.
5.3.1 Precautions for maintenance and inspection
For some short time after the power is switched off, a high voltage remains in the smoothing capacitor. When
accessing the inverter for inspection, switch power off. When more than 10 minutes have elapsed, make sure
that the voltage across the main circuit terminals P-N <
+
-
> of the inverter is 30VDC or less using a meter,
etc.
5.3.2 Check items
(
1
)
Daily inspections
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.
Note: Do not use solvent, such as acetone, benzene, toluene and alcohol, as they will cause the inverter
surface paint to peel off.
Do not use detergent or alcohol to clean the display and other sections of the operation panel
(FR-DU04) or parameter unit (FR-PU04) as these sections may deform.
5.3.3 Periodic inspection
Check the areas inaccessible during operation and requiring periodic inspection. For periodic inspection,
consult us.
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, relay: Check and change if necessary.
5