Nidec & Control Technique Commander SK Drive

Nidec & Control Technique Commander SK Drive Fault Codes:

Fault Code and Meaning	Cause and Remedy
UV DC bus under voltage	Cause: Low AC supply voltage. Low DC bus voltage when supplied by an external DC power supply. Remedy: Check power supply voltage and connections.
OV DC bus over voltage	Cause: Deceleration rate set too fast for the inertia of the machine. Mechanical load driving the motor. Remedy: Increase deceleration ramp time or install braking resistor.
OI.AC** Drive output instantaneous over current	Cause: Insufficient ramp times. Phase to phase or phase to ground short circuit on the drives output. Drive requires autotuning to the motor. Remedy: Check motor and motor cable for insulation resistance. If motor or motor connections changed, re-autotune drive to motor.
OI.br** Braking resistor instantaneous over current	Cause: Excessive braking current in braking resistor. Braking resistor value too small. Remedy: Check braking resistor value and wiring.
O.SPd Over speed	Cause: Excessive motor speed (typically caused by mechanical load driving the motor). Remedy: Check mechanical load and speed parameters.
tunE Auto tune stopped before completion	Cause: Run command removed before autotune complete. Remedy: Restart autotune and maintain run command.
It.br I2t on braking resistor	Cause: Excessive braking resistor energy. Remedy: Check braking cycle and resistor rating.
It.AC I2t on drive output current	Cause: Excessive mechanical load. High impedance phase to phase or phase to ground short circuit at drive output. Drive requires re-autotuning to motor. Remedy: Reduce load or check motor tuning.
O.ht1 IGBT over heat based on drives thermal model	Cause: Overheat software thermal model. Remedy: Check for blocked vents or fan failure.
O.ht2 Over heat based on drives heatsink	Cause: Heatsink temperature exceeds allowable maximum. Remedy: Reduce ambient temperature or check cooling fans.
th Motor thermistor trip	Cause: Excessive motor temperature. Remedy: Check motor cooling and load.
O.Ld1* User +24V or digital output overload	Cause: Excessive load or short circuit on +24 V output. Remedy: Check wiring on user I/O terminals.
O.ht3 Drive over-heat based on thermal model	Cause: Overheat software thermal model. Remedy: Check drive mounting and ventilation.
cL1 Analog input 1 current mode, current loss	Cause: Input current less than 3 mA when 4-20 or 20-4mA modes selected. Remedy: Check signal source and wiring.
SCL Serial communications loss time-out	Cause: Loss of communication when drive is under remote control. Remedy: Check serial communication cables and master controller.
EEF Internal drive EEPROM trip	Cause: Possible loss of parameter values. Remedy: Set default parameters (see Pr 29).
PH Input phase imbalance or input phase loss	Cause: One of the input phases has become disconnected from the drive (applies to 200/400 V three phase drives only, not dual rated drives). Remedy: Check input power supply fuses and wiring.
rS Failure to measure motors stator resistance	Cause: Motor too small for drive. Motor cable disconnected during measurement. Remedy: Check motor rating and connections.
CL.bt Trip initiated from the control word	Cause: Control word has initiated a trip. Remedy: Check remote control logic.
O.ht4 Power module rectifier over temperature	Cause: Power module rectifier temperature exceeds allowable maximum. Remedy: Check airflow and ambient temperature.
C.dAt SmartStick data does not exist	Cause: New/empty SmartStick being read. Remedy: Program the SmartStick or use one with valid data.
C.Acc SmartStick read/write fail	Cause: Bad connection or faulty SmartStick. Remedy: Re-seat SmartStick or replace it.
C.rtg SmartStick/drive rating change	Cause: Already programmed SmartStick read by a drive of a different rating. Remedy: Use SmartStick compatible with drive rating.
O.cL Overload on current loop input	Cause: Input current exceeds 25 mA. Remedy: Check analog input source.
HFxx trip Hardware faults	Cause: Internal drive hardware fault. Remedy: See Commander SK Advanced User Guide.
OVL.d I x t overload (I = current, t = time)	Cause: Motor current overload detected. Remedy: Reduce motor current (Load).
hot Heatsink/IGBT temperature high	Cause: Drive thermal model limits approached. Remedy: Reduce ambient temperature or reduce motor current.
br.rS Braking resistor overload	Cause: Braking resistor thermal limit approached. Remedy: See Menu 10 in the Commander SK Advanced User Guide.
AC.Lt Drive is in current limit	Cause: Load requires more current than the limit set. Remedy: See Menu 10 in the Commander SK Advanced User Guide.
FAIL Failed attempt to read stick	Cause: An attempt has been made to read the stick when the drive was not disabled or tripped, or the stick is read-only. Remedy: Ensure drive is disabled before reading SmartStick.