Unitronics UMI-B1 UL Series Operation Manual page 103

UMI-B1 UL Series Inverter
Checking part
Ventilating duct
6.1.1 Cooling fan
The inverter's cooling fan has a minimum life span of 25,000 operating hours. The actual
life span depends on the inverter usage and ambient temperature.
The operating hours can be found through P07.14 (accumulative hours of the inverter).
Fan failure can be predicted by the increasing noise from the fan bearings. If the inverter
is operated in a critical part of a process, fan replacement is recommended once these
symptoms appear. Replacement fans are available from UNITRONICS.
•
Read and follow the instructions in chapter Safety Precautions.
Ignoring the instructions would cause physical injury or death, or
damage to the equipment.
1. Stop the inverter and disconnect it from the AC power source and wait for at least the
time designated on the inverter.
2. Lever the fan holder off the inverter frame with a screwdriver and lift the hinged fan
holder slightly upward from its front edge.
3. Disconnect the fan cable.
4. Remove the fan holder from the hinges.
5. Install the new fan holder including the fan in reverse order.
6. Restore power.
6.1.2 Capacitors
Reforming the capacitors
The DC bus capacitors must be reformed according to the operation instruction if the
inverter has been stored for a long time. The storing time is counted from the producing
date other than the delivery data which has been marked in the serial number of the
inverter.
Checking item
Ensure there is no
color-changing caused
by overheating.
Ensure whether there
is stuff or foreign
objection in the cooling
fan, air vent.
101
Checking
method
Visual
examination or
estimate the
usage time NA
according to the
maintenance
information
Visual
NA
examination
Fault tracking
Criterion