LS Electric S100 Drive

Fault Code and MeaningCause and Remedy
OLt

Over Load (Latch)

Cause:

Displayed when the motor overload trip is activated and the actual load level exceeds the set level.



Remedy:

Check motor load and capacity. Operates when Pr.20 is set to a value other than 0.
ULt

Under Load (Latch)

Cause:

Displayed when the motor underload trip is activated and the actual load level is less than the set level.



Remedy:

Check for broken belts or pump dry run. Operates when Pr.27 is set to a value other than 0.
OCt

Over Current1 (Latch)

Cause:

Displayed when inverter output current exceeds 200% of the rated current.



Remedy:

Check for short circuits or motor insulation failure.
OVt

Over Voltage (Latch)

Cause:

Displayed when internal DC circuit voltage exceeds the specified value.



Remedy:

Check input voltage and deceleration time.
LVt

Low Voltage (Level)

Cause:

Displayed when internal DC circuit voltage is less than the specified value.



Remedy:

Check input power supply voltage.
LV2

Low Voltage2 (Latch)

Cause:

Displayed when internal DC circuit voltage is less than the specified value during inverter operation.



Remedy:

Check for power fluctuations during operation.
GFt

Ground Trip (Latch)

Cause:

Displayed when a ground fault trip occurs on the output side of the inverter and causes the current to exceed the specified value.



Remedy:

Check motor and cabling for ground faults. (Note: S100 inverters 4.0kW or less do not support GFT; they may show OCT or OVT instead).
EtH

E-Thermal (Latch)

Cause:

Displayed based on inverse time-limit thermal characteristics to prevent motor overheating.



Remedy:

Check motor load and cooling. Operates when Pr.40 is set to a value other than 0.
POt

Out Phase Open (Latch)

Cause:

Displayed when a 3-phase inverter output has one or more phases in an open circuit condition.



Remedy:

Check output wiring. Operates when bit 1 of Pr.05 is set to 1.
IPO

In Phase Open (Latch)

Cause:

Displayed when a 3-phase inverter input has one or more phases in an open circuit condition.



Remedy:

Check input wiring and fuses. Operates only when bit 2 of Pr.05 is set to 1.
IOL

Inverter OLT (Latch)

Cause:

Displayed when the inverter has been protected from overload and resultant overheating (150% for 1 min, 200% for 4 sec).



Remedy:

Check load duty cycle and inverter capacity.
ntH

No Motor Trip (Latch)

Cause:

Displayed when the motor is not connected during inverter operation.



Remedy:

Check motor connection. Operates when Pr.31 is set to 1.
OHt

Over Heat (Latch)

Cause:

Displayed when the temperature of the inverter heat sink exceeds the specified value.



Remedy:

Check cooling fan and ambient temperature.
OC2

Over Current2 (Latch)

Cause:

Displayed when the DC circuit in the inverter detects a specified level of excessive, short circuit current.



Remedy:

Check for short circuit in the motor or internal DC circuit issues.
EHt

External Trip (Latch)

Cause:

Displayed when an external fault signal is provided by the multi-function terminal.



Remedy:

Check external device status. Requires multi-function input terminals at In.65-71 set to 4.
bX

BX (Level)

Cause:

Displayed when the inverter output is blocked by a signal provided from the multi-function terminal.



Remedy:

Check input signal status. Requires multi-function input terminals at In.65-71 set to 5.
HWt

H/W-Diag (Fatal)

Cause:

Displayed when an error is detected in memory (EEPROM), ADC Offset, or CPU watchdog.



Remedy:

Fatal Error. Power cycle the unit. If error persists, contact LS ELECTRIC customer service.
ntC

NTC Open (Latch)

Cause:

Displayed when an error is detected in the temperature sensor of the Insulated Gate Bipolar Transistor (IGBT).



Remedy:

Contact service center.
FAn

Fan Trip (Latch)

Cause:

Displayed when an error is detected in the cooling fan.



Remedy:

Check or replace cooling fan. (Set Pr.79 to 0 to activate fan trip for models below 22kW).
PId

Pre-PID Fail (Latch)

Cause:

PID feedback is below set value and low feedback continues (treated as load fault).



Remedy:

Check PID feedback loop and system pressure/flow. Operates with functions set at AP.34–AP.36.
Hbr

Ext-Brake (Latch)

Cause:

Occurs when the inverter output starting current remains below the set value at Ad.41.



Remedy:

Check external brake settings. Set either OU.31 or OU.32 to 35 (BR Control).
SFA / SFb

Safety A(B) Err (Latch)

Cause:

Displayed when at least one of the two safety input signals is off.



Remedy:

Check safety input wiring and switches.
PtCt

PTC Trip (Latch)

Cause:

Displayed when a PTC error is detected, PTC value is exceeded, or a fault occurs.



Remedy:

Check motor PTC sensor and wiring.
LOr

Lost Command (Level)

Cause:

Frequency or operation command error detected during remote operation (not keypad).



Remedy:

Check communication lines. Activate by setting Pr.12 to any value other than 0.
IOt

IO Board Trip (Latch)

Cause:

I/O board or external communication card is not connected or has a bad connection.



Remedy:

Check connection of the option card.
ErrC

Error Code

Cause:

Displayed when an error code continues for more than 5 seconds.



Remedy:

Check specific error sequence displayed.
PAr

ParaWrite Trip (Latch)

Cause:

Communication fails during parameter writing (LCD keypad usage).



Remedy:

Check control cable connection between keypad and inverter.
OPt

Option Trip-1 (Latch)

Cause:

Communication error detected between the inverter and the communication board.



Remedy:

Check installation of communication option card.
OLW

Over Load Warning

Cause:

Displayed when the motor is overloaded.



Remedy:

Operates when Pr.17 is set to 1. Output available via terminal (OU.31/OU.33 set to 5).
ULW

Under Load Warning

Cause:

Displayed when the motor is underloaded.



Remedy:

Operates when Pr.25 is set to 1. Output available via terminal (OU.31/OU.33 set to 7).
IOLW

INV Over Load Warning

Cause:

Displayed when overload time equivalent to 60% of inverter overheat protection level is accumulated.



Remedy:

Reduce load. Output available via terminal (OU.31/OU.33 set to 6).
LCW

Lost Command Warning

Cause:

Lost command warning alarm occurs based on condition set at Pr.13-15.



Remedy:

Check comms. Even if Pr.12 is 0, this warning can occur via digital output (OU.31/OU.33 set to 13).
FAnW

Fan Warning

Cause:

Displayed when an error is detected from the cooling fan while Pr.79 is set to 1.



Remedy:

Check fan. Warning signal available via digital output (OU.31/OU.33 set to 8).
EFAn

Fan Exchange

Cause:

Alarm occurs when the fan life value (Pr.86) is less than the value set at Pr.87.



Remedy:

Replace fan. Warning signal available via digital output (OU.31/OU.33 set to 37).
dbW

DB Warn %ED

Cause:

Displayed when the DB resistor usage rate exceeds the set value.



Remedy:

Check DB resistor sizing. Set detection level at Pr.66.
trEr

Retry Tr Tune

Cause:

Tr tune error warning alarm is activated when motor’s rotor time constant (Tr) is too low or high.



Remedy:

Check motor parameters. Activated when dr.9 is set to 4.
SLP

PID Sleep

Cause:

When the PID operation enters sleep mode, a warning occurs.



Remedy:

Normal operation status during PID sleep.