Unit installation
74  ACZ / AGZ-BM  IOMM ACZ/AGZ-3 
Trip History and Inverter Status 
Always find the cause of the fault 
before clearing it. When a fault occurs, 
the inverter stores important perform-
ance data at the moment of the fault.  
To access the data, use the monitor 
functions (D_xx) and select D_08 for 
details about the present fault (E
n
), or 
the error code for the past two trip 
events (E
 n-1
) and E
 n-2
) using the D_09 
Trip History function. 
The following Monitor Menu map 
shows how to access the error codes.  
When fault(s) exist, you can review 
their details by first selecting the proper 
function: D_08 displays current trip 
data, and D09 displays trip history. 
VFD Monthly and Yearly Inspection Chart 
Frequency 
Item Inspected  Check for ... 
Month Year 
Inspection Method  Criteria 
Ambient 
environment 
Extreme Temperatures & 
humidity 
 Thermometer, hygrometer 
Ambient temperature 
between – 10 to 40°C, non-
condensing 
Major devices 
Abnormal noise & 
vibration 
  Visual & aural 
Stable environment for 
electronic controls 
Overall 
Power supply 
voltage 
Voltage tolerance 
Digital volt meter, measure 
between inverter terminals 
[L1], [L2], [L3} 
200V class: 
200 to 240V 50/60 Hz 
400V class: 
380 to 460V 50/60 Hz 
Ground Insulation  Adequate resistance   
Digital volt meter, GND to 
terminals 
5 Meg. Ohms or greater 
Mounting  No loose screws   
Torque wrench 
M3: 0.5 – 0.6 Nm 
M4: 0.98 – 1.3 Nm 
M5: 1.5 – 2.0 Nm 
Components Overheating   
Thermal trip events  No trip events 
Housing Dirt, dust   
Visual  Vacuum dust & dirt 
Terminal block  Secure connections   
Visual No abnormalities 
Smoothing 
capacitor 
Leading, swelling 
 Visual  No abnormalities 
Relay(s) Chattering   
Aural 
Single click when switching 
ON or OFF 
Resistors  Cracks or discoloring   
Visual 
Use Ohm meter to check 
braking resistors 
Noise 
  Power down, manually rotate  Rotation must be smooth 
Main 
circuit 
Cooling fan 
Dust 
  Visual  Vacuum to clean 
Overall 
No order, discoloring, 
corrosion 
Visual No abnormalities 
Control 
circuit 
Capacitor  No leaks or deformation 
 Visual  Undistorted appearance 
Display LEDs  Legibility 
  Visual  All LED segments work 










