Hi everyone,

There are two types of faults: Auto-Reset/Run and Non-Resetable. Auto-Reset/Run faults can be reset automatically if certain conditions are met, while Non-Resetable faults require manual correction before they can be cleared. The passage also describes the Auto Restart feature, which allows the drive to automatically reset certain faults and restart without user intervention. However, caution is advised when using this feature as it may cause the drive to start unexpectedly based on user-defined programming. It also explains how to clear a Type 1 fault and restart the drive, and clear an OverVoltage, UnderVoltage or Heatsink OvrTmp fault without restarting the drive.

 "F2 Auxiliary Input", that can occur in the drive. The fault is caused by the auxiliary input interlock being open. To resolve this fault, the user should first check the remote wiring and then verify the communications programming to see if the fault was intentional. It means that there may be a problem with the wiring or programming of the auxiliary input, and the user should check these elements to determine the cause of the fault and take corrective action.


 "F3 Power Loss", that can occur in the drive. The fault is caused by excessive DC Bus voltage ripple. To resolve this fault, the user should first monitor the incoming line for phase loss or line imbalance, and then check the input line fuse. This fault indicates that there may be a problem with the power supply to the drive, such as a loss of power or an imbalance in the voltage. The user should check these elements to determine the cause of the fault and take corrective action.


"F4 UnderVoltage", that can occur in the drive. The fault is caused by the DC bus voltage falling below the minimum value. To resolve this fault, the user should monitor the incoming AC line for low voltage or line power interruption. This fault indicates that there may be a problem with the power supply to the drive, such as a low voltage or an interruption in power. The user should check these elements to determine the cause of the fault and take corrective action.


, "F5 OverVoltage", that can occur in the drive. The fault is caused by the DC bus voltage exceeding the maximum value. To resolve this fault, the user should monitor the AC line for high line voltage or transient conditions. Bus overvoltage can also be caused by motor regeneration, such as when the motor is slowing down and returning energy to the bus. To prevent this, the user can extend the decel time (deceleration time) or install dynamic brake option in the drive. This fault indicates that there may be a problem with the power supply to the drive, such as a high voltage or a transient condition. The user should check these elements to determine the cause of the fault and take corrective action.


"F6 Motor Stalled" is a type of fault that occurs when the drive is unable to accelerate the motor. This can be caused by a number of factors, including excessive load or a current limit that is set too low. To resolve this type of fault, the user can try increasing P109 and/or A402 [Accel Time x], or reducing the load on the motor so that the drive's output current does not exceed the current limit set by parameter A441 [Current Limit]. Additionally, the user can check the motor and drive wiring, and ensure that the motor is properly connected and configured.

"F7 Motor Overload" is an error that occurs when the drive detects that the current flowing through the motor exceeds the value set by parameter P103 [Motor OL Current]. To resolve this issue, the user should take the following steps:

Reduce the load on the motor so that the drive output current does not exceed the current set by parameter P103 [Motor OL Current].
Verify the setting of A453 [Boost Select], as this parameter affects the motor current level. Make sure it is set correctly for the application.


 "F8 Heatsink Over Temperature" indicates that the temperature of the heatsink, which is a component that helps dissipate heat from the device it is attached to, has exceeded a predefined value. To troubleshoot this issue, the first step is to check for blocked or dirty heat sink fins, which can impede the proper flow of air and cause the temperature to rise. Additionally, it is important to verify that the ambient temperature in the area where the device is installed has not exceeded the maximum allowable temperature for that type of installation. For example, for IP30/NEMA 1/UL Type 1 installations, the maximum allowable temperature is 40°C (104°F), while for IP20/Open type installations, it is 50°C (122°F). If the problem persists, check the fan.


The error message "F12 HW OverCurrent" indicates that the drive output current (the current flowing through the electronic device) has exceeded the hardware current limit. This can happen for a number of reasons, such as excess load on the device, improper settings, or other causes of excess current. To troubleshoot this issue, the first step is to check the programming of the device to ensure it is properly configured. Additionally, check for any excess load on the device, verify that the A453 [Boost Select] setting is correct, ensure that the DC brake volts are not set too high, and investigate any other potential causes of excess current.


"F13 Ground Fault" is an error that occurs when a current path to earth ground is detected at one or more of the drive output terminals. This could indicate a problem with the motor or external wiring. To troubleshoot this issue, you should check the motor and external wiring to the drive output terminals for a grounded condition. This could include inspecting the wiring for any damage or frayed wires, and ensuring that all connections are secure and properly connected. If the problem persists, it may be necessary to replace the motor or other components to resolve the issue.

"F33 Auto Restart Tries" is an error that occurs when the drive (an electronic device used to control the speed and torque of an electric motor) unsuccessfully attempts to reset a fault and resume running for the programmed number of auto restart tries. This error indicates that there is a problem that is preventing the drive from operating properly, and that the problem has not been resolved despite the drive's attempts to automatically reset itself.

To troubleshoot this issue, you should first identify and correct the cause of the fault. This may involve checking the wiring and connections, inspecting the motor for damage, and checking any other system components that may be causing the problem. Once the cause of the fault has been identified and corrected, you will need to manually clear the error by resetting the drive or cycling power to the system. If the problem persists it may be necessary to replace the drive or other components.



"F38 Phase U to Gnd, F39 Phase V to Gnd, F40 Phase W to Gnd",   is an error that occurs when a phase to ground fault is detected between the drive and the motor in the phase "U" (the phase U refers to one of the three phase line of a 3-phase power supply, usually labeled U, V and W). A phase to ground fault means that there is a current flow between a phase conductor and the ground. This could indicate a problem with the wiring between the drive and the motor or a problem with the motor itself.

To troubleshoot this issue, you should:

Check the wiring between the drive and motor. Ensure that all connections are secure and properly connected, and that there is no damage or frayed wires.
Check the motor for a grounded phase. A grounded phase can cause a phase to ground fault.
Replace the drive if the fault cannot be cleared. If the problem persists after checking the wiring and the motor, it may be necessary to replace the drive.
It is important to note that a phase to ground fault can also be caused by a problem with the power supply. If the problem persists after checking the wiring and the motor, it may be necessary to check the power supply for any issues.


"F41 Phase UV Short, F42 Phase UW Short, and F43 Phase VW Short" are all errors that occur when excessive current is detected between two specific output terminals. These errors indicate a problem with the wiring between the drive and the motor or a problem with the motor itself, such as a short circuit.

To troubleshoot these issues, you should:

Check the motor and drive output terminal wiring for a shorted condition. Ensure that all connections are secure and properly connected, and that there is no damage or frayed wires. Also, check the motor windings for any short circuit.
Replace the drive if the fault cannot be cleared. If the problem persists after checking the wiring and the motor, it may be necessary to replace the drive.
It's important to note that these errors are specific to the terminals that are indicated, for example, F41 Phase UV Short means there is excessive current between terminals U and V. So, it's important to check the wiring and connections of the specific terminals that are indicated in the error message.

F48 Params Defaulted is an error that occurs when the drive is commanded to write default values to EEPROM (Electrically Erasable Programmable Read-Only Memory). EEPROM is a type of non-volatile memory that is used to store the drive parameters and settings. This error indicates that the drive's parameters have been reset to their default values, and the drive will need to be reprogrammed before it can be used.

To troubleshoot this issue, you should:

Clear the fault or cycle power to the drive. This can be done by turning off the power to the drive and then turning it back on again.
Program the drive parameters as needed. This will involve entering the appropriate values for the drive's parameters, such as the motor's speed, voltage, and current. It's important to verify that all the parameters are correctly set before putting the drive into operation.
It's important to note that if the drive defaults the parameters, it could be indicating a problem with the internal memory of the drive. In this case, it's recommended to check the drive's manual or contact the manufacturer for further assistance.

"F63 SW OverCurrent" is an error that occurs when the drive's current exceeds the value set by the software parameter "A448 [SoftWare Current Trip]". This error is a software protection that limits the drive's current to a safe level to protect the drive and the connected load.

To troubleshoot this issue, you should:

Check the load requirements. Make sure that the load connected to the drive does not exceed the drive's current rating. If the load is too high, it could cause the drive to exceed the current limit set by A448.

"Check the A448 [SW Current Trip]" setting. Verify that the current limit set in the software parameter is appropriate for the load connected to the drive. If the current limit is set too low, it could cause the drive to trip on overcurrent even though the load is within the drive's capabilities.

It's important to note that this error could also indicate a problem with the drive's power supply or the load connected to the drive. If the problem persists after checking the load requirements and the A448 setting, it may be necessary to check the power supply and the load for any issues.

"F64 Drive Overload" is an error that occurs when the drive's current exceeds the drive's overload rating. The overload rating is the maximum current that the drive can handle for a certain period of time without causing damage. Typically, most drives have a rating of 150% for 1 minute or 200% for 3 seconds.

To troubleshoot this issue, you should:

Reduce the load on the drive. Make sure that the load connected to the drive does not exceed the drive's current rating. If the load is too high, it could cause the drive to exceed the overload rating.

Extend the Accel Time. The acceleration time is the amount of time it takes for the drive to reach the full speed. If the acceleration time is too short, the drive may exceed its overload rating. Increasing the acceleration time will reduce the current required to reach the target speed, thus reducing the risk of overloading the drive.

It's important to note that this error could also indicate a problem with the drive's power supply, the load connected to the drive or the controller settings. If the problem persists after checking the load requirements and the acceleration time, it may be necessary to check the power supply, the load and the controller settings for any issues.

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