GE VAT20 Series Instruction Manual page 34

4-3 Manual Reset and Auto-Reset Operative faults
INDICATION
OCS
OCA
OCC
OCd
OCb
OVC
LVC
OHC
CONTENT POSSIBLE CAUSE
Transient 1. Motor coil short -circuit with
over-current external casing
starting machine 2. Motor connection wire
short-circuit with grounding
3. Transistor module
damaged
Over-current at 1. Acceleration time setting
acceleration too short
2. Improper V/F feature
selection
3. Applied motor capacity
exceeds inverter capacity
Over-current at 1. Transient alteration of the
steady speed loading
2. Transient alteration of the
power supply
Over-current at Deceleration setting too short
deceleration
Over-current at DC Breaking frequency,
breaking breaking voltage, or
breaking time setting too
long
Over-voltage at 1. Deceleration time setting
operation/deceler too
ation loading too large
2. Power
variation too large
Insufficient 1. Power supply voltage too
voltage level at low
operation 2. Power supply voltage
variation too large
Heat -sink over 1. Loading too heavy
heated at 2. Ambient temperature too
operation high or poor ventilation
short or inertial
supply voltage
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COUNTERMEASURE
1. Examining motor
2. Examining wiring
3. Replace transistor module
1. Adjust acceleration time to
longer setting
2. Adjust to a proper V/F curve
3. Replace and install another
inverter with appropriate
capacity
1. Examining the loading
configuration
2. Install inductor on the power
supply input side
Adjust to use a longer
acceleration time
Adjust to reduce settings of
Fn_15, Fn_16, or Fn_17
1. Adjust to use a longer
deceleration time
2. Install a inductor on the power
supply input side
3. Increase the capacity of
inverter
1. Improve power source quality
2. Adjust to use a longer
acceleration time
3. Increase capacity of inverter
4. Install a reactor on the power
supply input side
1. Examining the loading
2. Increase capacity of inverter
3. Improve ventilation