CHAPTER 14 - TROUBLESHOOTING & MAINTENANCE
14.1 Protective functions
When a fault occurs, the cause must be corrected before the fault can be cleared. If
protective function keeps active, it could lead to reduction in product life and damage to the
equipment.
Fault Display and information
Overcurrent
The inverter turns off its output when the output current of the inverter
flows greater than the inverter rated current.
Overcurrent2
When IGBT’s Arm is short and output short occurs, the inverter turns off
The inverter turns off its output when a ground fault occurs and the
ground fault current is greater than the internal setting value of the
The inverter turns off its output when the output current of the inverter
flows greater than the rated level (150% for 1 minute).
The inverter turns off its output if the output current of the inverter flows at
150% of the inverter rated current for more than the current limit time (1 min).
Inverter
overheat
The inverter turns off its output if the heatsink overh
eats due to a
damaged cooling fan or an alien substance in the cooling fan by
detecting the temperature of the heatsink.
The inverter turns off its output when one or more of the output (U, V,
W) phase is open. The inverter detects the output current to check the
phase loss of the output.
The inverter turns off its output if the DC voltage of the DC BUS
exceeds 400V for 2S/T class and 820V for 4T class when the motor
decelerates. This fault can also occur due to a surge voltage generated
at the power supply system.
The inverter turns off its output if the DC voltage drops below 180V for
2S/T class and 360V for 4T class because
insufficient torque or
overheating of the motor can occur when the input voltage of the
inverter drops.
The internal electronic thermal of the inverter determines the
overheating of the motor. If the motor is overloaded the inverter turns
off the output. The inverter cannot protect the motor when driving a
motor having more than 4 poles or multi motors.
loss
Inverter output is blocked when one of R, S, T is open or the electrolytic
capacitor needs to be replaced.