Yaskawa E7B Drive Bypass - Manual (Page 211)

Maintenance 7 - 3
Preventive Maintenance
If the Drive is used under the following conditions, it may be necessary to inspect more often:
• High ambient temperatures, humidity or altitudes above 3,300 feet
• Frequent starting and stopping
• Fluctuations of the AC power supply or load
• Excessive vibration and/or shock loading
• Poor environment, including dust, metal particles, salt, sulfuric acid, and chlorine
Table 7.3 Preventive Maintenance
Inspection Points Item Check Points Every 3-6 Months Yearly
General
Environment
Ambient Temperature
Humidity
Dust
Harmful Gas
Oil Mist
X
X
X
X
X
Equipment Abnormal vibration or noise X
AC Power Supply Main circuit & control voltage X
AC Power Circuit &
Devices
Conductors & Wire
Connections
Loose lugs, screws & wires
Hot spots on parts
Corrosion
Bent conductors
Breakage, cracking or discoloration
Check spacing
X
X
X
X
X
X
Transformers & Reactors Discoloration or Noise X
Terminal Blocks Loose, damaged X
DC Bus Capacitors
Leakage
Ruptures, broken, expansion
Capacitance & insulation resistance
X
X
X
Relays & Contactors
Noisy
Contact discoloration
X
X
Soft Charge Resistors
Cracked
Discoloration
X
X
Control Circuits Operation
Speed reference voltage/current
I/O contact operation
Relay logic
X
X
Cooling System Cooling Fans/Fins & Heatsink
Abnormal fan noise
Loose connectors
Free of accumulation
X
X
X
Keypad/Front Panel
Display
Digital Operator and
Front Panel
LEDs
Monitor display values
Key and selector switch functionality
Clean
X
X
X
X