Toshiba G7 Drives

Fault Code and MeaningCause and Remedy
CM1
Comm1 Error

Cause:

Internal communications error.


Remedy:


  • Improperly programmed ASD.

  • Improper communications settings.

  • Improperly connected cables.


CM2
Comm2 Error

Cause:

External communications error.


Remedy:


  • Check external communication connections.

  • Verify communication settings.


EMG
Emergency Off

Cause:

Output signal from the ASD is terminated and a brake may be applied if so configured.


Remedy:


  • Stop|Reset pressed twice at the EOI.

  • EOFF command received remotely.

  • ASD reset required.


MOFF
Main Undervoltage

Cause:

Undervoltage condition at the 3-phase AC input to the ASD.


Remedy:


  • Check for low 3-phase utility voltage.


OC
Over Current

Cause:

ASD output current greater than F601 setting.


Remedy:


  • Defective IGBT (U, V, or W).

  • ASD output to the motor is connected incorrectly. Disconnect the motor and retry.

  • ASD output phase-to-phase short.

  • The ASD is starting into a spinning motor.

  • Motor/machine jammed.

  • Mechanical brake engaged while the ASD is starting or while running.

  • Accel/Decel time is too short.

  • Voltage Boost setting is too high.

  • Load fluctuations.

  • ASD operating at an elevated temperature.


OH
Overheat

Cause:

ASD ambient temperature excessive.


Remedy:


  • ASD is operating at an elevated temperature.

  • ASD is too close to heat-generating equipment.

  • Cooling fan vent is obstructed.

  • Cooling fan is inoperative.

  • Internal thermistor is disconnected.


OJ
Timer

Cause:

Run-time counter exceeded.


Remedy:


  • Type Reset required; select Clear run timer.


OLI
ASD Overload

Cause:

Load requirement in excess of the capability of the ASD.


Remedy:


  • The carrier frequency is too high.

  • An excessive load.

  • Acceleration time is too short.

  • DC damping rate is set too high.

  • The motor is starting into a spinning load after a momentary power failure.

  • The ASD is improperly matched to the application.


OLM
Motor Overload

Cause:

Load requirement in excess of the capability of the motor.


Remedy:


  • V/f parameter improperly set.

  • Motor is locked.

  • Continuous operation at low speed.

  • The load is in excess of what the motor can deliver.


OLR
Resistor Overload

Cause:

Excessive current at the Dynamic Braking Resistor.


Remedy:


  • Deceleration time is too short.

  • DBR configuration improperly set.


OP
Overvoltage

Cause:

DC bus voltage exceeds specifications.


Remedy:


  • ASD attempting to start into a spinning motor after a momentary power loss.

  • Incoming utility power is above the specified range.

  • Decel time is too short.

  • Voltage spikes at the 3-phase input; install inductive filter.

  • DBR required or DBR resistance value is too high.

  • DBR function is turned off.

  • Overvoltage Stall feature is turned off.

  • System is regenerating.

  • Load instability.

  • Disable the Ridethrough function (F302).


OT
Overtorque

Cause:

Torque requirement in excess of the setting of F616 or F617 for a time longer than the setting of F618.


Remedy:


  • ASD is not correctly matched to the application.

  • F616 or F617 setting is too low.

  • Obstructed load.


POFF
Control Undervoltage

Cause:

Undervoltage condition at the 5, 15, or the 24 VDC supply.


Remedy:


  • Defective Control board.

  • Excessive load on power supply.

  • Low input voltage.


PtSt
Reference Point

Cause:

Two speed-reference frequency setpoint values are too close to each other.


Remedy:


  • Two speed reference frequency setpoints are too close to each other (increase the difference).


UC
Undercurrent

Cause:

Output current of the ASD is below the level defined at F611 and remains there for the time set at F612.


Remedy:


  • Check load coupling (load loss).

  • Check F611 and F612 settings.


Autotune Error
Autotune Malfunction

Cause:

Autotune readings that are significantly inconsistent with the configuration information.


Remedy:


  • A non-3-phase motor is being used.

  • Incorrect settings at F400, F413, or F414.

  • Using a motor that has a significantly smaller rating than the ASD.

  • ASD output cabling is too small, too long, or is being housed in a cable tray with other cables that are producing an interfering EMF.

  • Motor is running during the Autotune function.


Communication Error
Comms Malfunction

Cause:

System communication failure.


Remedy:


  • Communication malfunction.

  • Improper or loose connection.

  • Improper system settings.


CPU Fault
Processor Error

Cause:

Internal processor error.


Remedy:


  • CPU malfunction.

  • Contact Toshiba support.


DC Bus Undervoltage
Bus Voltage Low

Cause:

DC Bus voltage dropped below limit.


Remedy:


  • 3-phase input voltage low.

  • Defective control board.

  • Excessive load on the power supply.

  • Undervoltage/Ridethrough settings require adjustment.


DC Fuse Open
Internal Fuse Blown

Cause:

Internal DC bus fuse is open.


Remedy:


  • Check internal fuses.

  • Check for shorts.


Dynamic Braking Resistor Overcurrent
DBR Overcurrent

Cause:

ASD inability to discharge the bus voltage during regeneration.


Remedy:


  • No dynamic braking resistor (DBR) installed.

  • Deceleration time is too short.

  • Improper DBR setup information.

  • Defective IGBT7 (or IGBT7 ckt.).

  • 3-phase input voltage is above specification.


Earth Fault
Ground Fault

Cause:

Current leakage to Earth Ground detected.


Remedy:


  • Ground fault at the motor.

  • Ground fault at the output of the ASD.

  • Current leakage to Earth Ground.


EEPROM Data Fault
Memory Error

Cause:

Internal EEPROM malfunction.


Remedy:


  • Cycle power. If fault persists, replace control board.


Encoder Loss
Signal Missing

Cause:

Encoder signal missing while running during closed-loop operation.


Remedy:


  • Check encoder connections.

  • Check encoder power supply.


Gate Array Fault
Hardware Failure

Cause:

Defective Gate Array or Gate Array malfunction.


Remedy:


  • Contact service representative.


Input Phase Loss
Phase Missing

Cause:

3-phase input to the ASD is low or missing.


Remedy:


  • Check incoming power fuses and connections.


Load Drooping
Load Error

Cause:

Load requirement is in excess of the capabilities of the motor.


Remedy:


  • Check load mechanics.

  • Verify motor sizing.


Load End Short Circuit
Output Short

Cause:

Improper wiring at the ASD output to the motor.


Remedy:


  • Check motor wiring for shorts.


Low Current
Current Low

Cause:

Improper Low Current detection level setting.


Remedy:


  • Adjust low current detection parameters.


Option Fault
Card Error

Cause:

Optional device malfunction.


Remedy:


  • Improper system settings (at ASD or optional device).

  • Loose or improper connection.


Output Phase Loss
Motor Phase Lost

Cause:

3-phase output from the ASD is low or missing.


Remedy:


  • Output current is not within specified limits.

  • Loose or improper ASD-to-motor connection.


Overcurrent During Acceleration
Accel OC

Cause:

Overcurrent detected while ramping up speed.


Remedy:


  • V/f setting needs to be adjusted.

  • Restart from a momentary power outage.

  • The ASD is starting into a rotating motor.

  • ASD/Motor not properly matched.

  • Phase-to-phase short (U, V, or W).

  • Accel time too short.

  • Voltage Boost setting is too high.

  • Motor/machine jammed.

  • Mechanical brake engaged while the ASD is running.


Overcurrent During Deceleration
Decel OC

Cause:

Overcurrent detected while ramping down speed.


Remedy:


  • Phase-to-phase short (U, V, or W).

  • Deceleration time is too short.

  • Motor/machine jammed.

  • Mechanical brake engaged while the ASD is running.


Overcurrent During Run
Run OC

Cause:

Overcurrent detected at constant speed.


Remedy:


  • Load fluctuations.

  • ASD is operating at an elevated temperature.


Over Speed
Speed Limit Exceeded

Cause:

Result of a motor speed that is greater than the commanded speed when using an encoder for speed control.


Remedy:


  • Improper encoder connection or setup information.

  • Defective encoder.


PG Type/Connection Error
Encoder Error

Cause:

ASD is configured to receive a signal from a shaft-mounted encoder and no signal is being received.


Remedy:


  • Disconnection at the Encoder circuit.

  • Motor is stopped and is generating torque via torque limit control.

  • ASD is not configured properly.


Phantom Fault
System Fault

Cause:

In a multiple ASD configuration a faulted ASD signals the remaining ASDs that a fault has occurred.


Remedy:


  • Check other ASDs in the system for the primary fault.


Position Deviation Error
Position Error

Cause:

Operating in the Position Control mode and the resulting position exceeds the limits of the F631 setting.


Remedy:


  • Check position loop settings.

  • Check mechanical linkage.


Sink/Source Setting Error
Jumper Error

Cause:

Logic setting mismatch.


Remedy:


  • Improperly positioned Sink/Source jumper on the control board or on an option device.

  • Sink/Source configuration of an option device is incorrect.


Torque Proving Fault
Brake Logic Error

Cause:

Torque proving logic failed.


Remedy:


  • Lift-First Pulse Count (F743) adjustment required.


Typeform Error
Firmware Mismatch

Cause:

Firmware information loaded into the Gate Driver board is inconsistent with the device.


Remedy:


  • The Gate Driver board has been replaced.

  • The Gate Driver board is defective.


U/V/W Phase Short Circuit
Output Short

Cause:

Low impedance at the U, V, or W lead of the ASD output.


Remedy:


  • Check for short circuit in motor cable or motor windings.

  • Check IGBTs.