YASKAWA H6B1A002, Technical Reference

Page: 557 / 794

Periodic
Inspection
and
Maintenance
8
8.2 Inspection
YASKAWA SIEPYAIH6B01A HV600 AC Drive Bypass Technical Reference 557
DANGER! Electrical Shock Hazard. Do not examine, connect, or disconnect wiring on an energized bypass. Before servicing,
disconnect all power to the equipment and wait for the time specified on the warning label at a minimum. The internal capacitor
stays charged after the bypass is de-energized. The charge indicator LED extinguishes when the DC bus voltage decreases below
50 Vdc. When all indicators are OFF, remove the covers before measuring for dangerous voltages to make sure that the bypass is
safe. If you do work on the bypass when it is energized, it will cause serious injury or death from electrical shock.
Table 8.2 Main Circuit Periodic Inspection Checklist
Inspection Area Inspection Points Corrective Action Checked
General
• Examine equipment for discoloration from too
much heat or deterioration.
•
Examine for damaged parts.
• Replace damaged components as necessary.
• The drive does not have many serviceable parts and it could be necessary to
replace the drive.
Examine for dirt, unwanted particles, or dust on
components.
•
Examine enclosure door seal.
• Use a vacuum cleaner to remove unwanted particles and dust without touching
the components.
• If you cannot remove unwanted particles and dust with a vacuum cleaner,
replace the components.
Conductors and
Wiring
• Examine wiring and connections for discoloration
or damage. Examine wiring and connections for
discoloration from too much heat.
• Examine wire insulation and shielding for
discoloration and wear.
Repair or replace damaged wiring.
Terminal Block
Examine terminals for stripped, damaged, or loose
connections.
• Tighten loose screws.
• Replace damaged screws or terminals.
Electromagnetic
Contactors and
Relays
• Examine contactors and relays for too much noise
during operation.
•
Examine coils for signs of too much heat, such as
melted or broken insulation.
•
Check coil voltage for overvoltage or undervoltage conditions.
•
Replace broken relays, contactors, or circuit boards that you can remove.
Electrolytic capacitor
• Examine for leaks, discoloration, or cracks.
• Examine if the cap has come off, if there is
swelling, or if there are leaks from broken sides.
The drive does not have many serviceable parts and it could be necessary to replace
the drive.
Diodes, IGBT (Power
Transistor) Examine for dust or other unwanted material collected
on the surface. Use a vacuum cleaner to remove unwanted particles and dust without touching the
components.
Table 8.3 Motor Periodic Inspection Checklist
Inspection Area Inspection Points Corrective Action Checked
Operation Check Check for increased vibration or unusual noise. Stop the motor and contact approved maintenance personnel as necessary.
Table 8.4 Control Circuit Periodic Inspection Checklist
Inspection Area Inspection Points Corrective Action Checked
General
•
Examine terminals for stripped, damaged, or loose
connections.
• Make sure that all terminals have been correctly
tightened.
• Tighten loose screws.
• Replace damaged screws or terminals.
• If terminals are integral to a circuit board, it could be necessary to replace the
control board or the drive.
Circuit Boards
• Check for odor, discoloration, or rust.
• Make sure that all connections are correctly
fastened.
• Make sure that the surface of the circuit board does
not have dust or oil mist.
•
Tighten loose connections.
•
Use a vacuum cleaner to remove unwanted particles and dust without touching
the components.
• If you cannot remove unwanted particles and dust with a vacuum cleaner,
replace the components.
•
Do not use solvents to clean the board.
•
The drive does not have many serviceable parts and it could be necessary to
replace the drive.
Table 8.5 Cooling System Periodic Inspection Checklist
Inspection Area Inspection Points Corrective Action Checked
Cooling fan
• Check for unusual oscillation or unusual noise.
• Check for damaged or missing fan blades.
Clean or replace the fans as necessary.
Heatsink
• Examine for dust or other unwanted material
collected on the surface.
•
Examine for dirt.
Use a vacuum cleaner to remove unwanted particles and dust without touching the
components.
Air Duct
Examine air intake, exhaust openings and make sure
that there are no unwanted materials on the surface.
Clear blockages and clean air duct as necessary.