Protective Functions - LS Starvert-iG5A Maintenance Manual

Protective functions

Trip
Type Function
Name
Over
OCT
Current
Over
OC2
current
Over
OLT
load
Ground
GFT
trip
Current
Inverter
IOLT over
load
Electronic
ETH
thermal
Over
OVT
voltage
Low
LVT
voltage
Voltage
Braking
-
operation
Description
Inverter output current exceeds 200 % of the
rated current.
Inverter detects a IGBT Arm short circuit or an
output short circuit.
The current value exceeds the motor's rated
current. (Default value = 180 % of the motor's
rated current)
The sum of 3 phases current(Normal 0V) is
higher than the level which is set and flowing
through inverter output for the setting time.
The inverter is operating at 150 % of the rated
current for more than 60 sec or at 200 % of
the rated current for 10 sec (this feature has
inverse time characteristics).
Stops the inverter operation to protect the
motor when a current exceeding the motor
rated current is supplied for a specific period
of time (Default value = 150 % of the motor's
rated current detected for 60 sec. This feature
has inverse time characteristics).
The inverter output current exceeds the
motor's rated current
The internal DC circuit voltage exceeds the
specified value.
200 V: 400 Vdc
400 V: 820 Vdc
The internal DC circuit voltage is less than the
specified value.
200 V: 180 Vdc (Reset level: 230 Vdc)
400 V: 360 Vdc (Reset level: 460 Vdc)
IGBT braking is turned on as DC voltage has
combined with regenerated voltage and
exceeds the specified voltage.
Turn On: 200 Vdc-390 Vdc , 400 Vdc-780 Vdc
Turn Off: 200 Vdc-380 Vdc , 400 Vdc-760 Vdc
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Fault trip troubleshooting
Display Cause
 Deceleration time is too
short.
 The inverter output current
exceeds the rated
capacity.
 The motor's mechanical
brake is operating
Over
improperly.
current
 Over current occurs when
the inverter power is
turned on.
 The actual current value is
different from the value
displayed.
 IGBT phase to phase fault.
 There is a short circuit in
the wiring on the output
side.
Over current2
 Motor oput cables are too
(Arm short)
long.
 Surge voltages occur at
the output terminals.
 A ground fault has
occurred in the output side
of the inverter.
 Phase to phase difference
of output voltage has
Ground trip
occurred.
 The motor's insulation is
damaged.
 Cooling system fault.
 Cooling fan fault.
 The ambient temperature
around the panel is too
Over heat
high.
 The carrier frequency is
too high.
Cooling fan faults can be inspected by sound and
Fan trip
the exterior condition. If the fan is malfunctioning,
Note
it may damage the inverter.
Remedy
 Set the Acc/Dec time.
 Decrease the load or
replace the inverter with a
higher-rated model.
 Check the mechanical
brake.
 Adjust the torque boost.
 Contact the supplier.
 Check for a phase to
phase short circuit at the
the IGBT.
 Check the output cables.
 Use the correct length for
motor cables.
 Reduce the carrier
frequency.
 Resolve the surging
voltage condition.
 Check the output cables.
 Check the voltages
between the phases are
balanced.
 Check the motor's
insulation resistance.
 Check that foreign objects
are obstructing the vent.
 Replace the cooling fan.
 Reduce the ambient
temperature to below 50
℃.
 Reduce the carrier
frequency.
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