Vacon NXS/NXP

The drive has detected an excessively high current (>4*IH) flowing in the motor cable, which can be caused by a sudden heavy load increase, a short circuit in the motor cables, or an incorrectly sized motor. This condition can lead to severe damage to the motor, cables, or the drive's internal power components if not promptly addressed.

The DC-link voltage within the drive has exceeded its predefined safe operating limits. Common causes include overly short deceleration times, high overvoltage spikes from the incoming AC supply, or a very rapid Start/Stop sequence. Sustained overvoltage can lead to critical damage to the drive's DC-link capacitors and IGBTs.

The drive's current measurement system has detected that the sum of the motor phase currents is not zero, indicating a leakage current to earth. This is typically a result of insulation malfunction within the motor windings or the motor cables. An unresolved earth fault poses a significant electrical safety hazard and can cause severe damage to both the motor and the drive.

The internal charging switch, which is responsible for pre-charging the DC-link capacitors, remains open when a START command is given. This indicates either an operational malfunction or a defective internal component within the drive. If this fault persists, the drive will be unable to start and operate, signaling a serious internal hardware issue.

An emergency stop signal has been received from an option board, causing the drive to immediately halt operation. This is a critical safety interlock feature. The drive will remain stopped and will not accept new run commands until the emergency stop condition is cleared and the integrity of the safety circuit is verified.

This fault indicates a severe internal component defect, potentially related to a short-circuited or overloaded brake resistor. It's a critical fault that prevents normal drive operation and requires immediate, specialized attention. Attempting to restart the drive or reconnect power without addressing the root cause risks further catastrophic damage to the unit.

This fault indicates a component failure or faulty operation within the frequency converter system. Subcodes in T.14 provide more specific information, such as issues with motor voltage feedback (S1), ASIC trip (S4), VaconBus disturbance (S5), charging switch (S6, S7), power unit communication (S9, S10, S11), or lack of power to the driver card (S8). If not resolved, it indicates an internal hardware or communication issue.

The DC-link voltage has fallen below its acceptable operating limits. This can be caused by a low incoming supply voltage, a defective input fuse, an external charge switch failing to close, or an internal AC drive fault. Prolonged undervoltage can cause erratic drive behavior, prevent proper starting, and potentially stress internal components.

The input line phase supervision has detected that one or more input line phases are missing. Subcodes in T.14 can specify if the issue relates to diode supply (S1) or active front end (S2) phase supervision. This prevents proper charging of the DC bus and operation of the drive.

The current measurement system has detected that there is no current flowing in one of the motor phases. This typically indicates an open circuit condition in the motor cables or within the motor windings, which can lead to motor damage or uncontrolled operation.

This fault indicates a problem with the braking system, specifically that no brake resistor is installed, the installed brake resistor is broken (open circuit), or there is an internal failure within the brake chopper itself. The drive cannot dissipate regenerative energy during deceleration without a functioning brake resistor and chopper.

The heatsink temperature of the frequency converter has fallen below –10 °C. Operating the drive outside its specified temperature range can impact component performance and lifespan.

The drive's heatsink temperature has exceeded its maximum safe operating limit (e.g., 90 °C or 77 °C for specific models). This is commonly caused by inadequate cooling airflow, accumulation of dust on heatsinks, high ambient temperatures, or an excessive switching frequency relative to the motor load. Sustained overtemperature will severely degrade and damage the drive's power components.

The motor has stalled, meaning it is not rotating despite receiving a run command. This is typically due to an excessive mechanical load or an obstruction preventing rotation. A stalled motor will draw very high current, leading to rapid overheating of the motor windings and potentially the drive's output stage.

The frequency converter's internal motor temperature model has detected overheating in the motor, typically due to prolonged overload. Continued operation under this condition will damage motor windings and insulation.

The motor underload protection has tripped, indicating that the motor is operating with insufficient mechanical load or no load at all. This can be caused by a broken belt, pump cavitation, an uncoupled shaft, or a process anomaly. Operating in an underload condition can sometimes lead to drive instability or signify a mechanical issue that requires attention.

An unbalance has been detected between power modules within paralleled power units. This signifies a discrepancy in current sharing or performance among the modules, which can lead to uneven wear and a reduced lifespan of the power components. If persistent, this fault indicates an internal issue within the paralleled power system.

An error occurred during the saving of parameters to the EEPROM, or the checksum of the stored parameters is incorrect. This indicates a potential operational malfunction or a defective memory component within the drive. This fault can lead to the loss of drive parameters, causing the drive to operate with default or incorrect settings.

The drive's internal counters are displaying incorrect values, which suggests a potential data corruption or an internal processing error. While not immediately critical to motor operation, inaccurate counter data can lead to incorrect system logging or misdiagnosis. This fault usually points to an internal software or hardware issue with the control unit.

The drive's internal microprocessor watchdog has triggered, indicating that the control software or hardware has become unresponsive or entered an unexpected state. This can be due to an operational malfunction or a defective internal component. A persistent watchdog fault prevents proper drive control and operation.

The drive's start-up sequence has been inhibited, typically because a run request signal was active while a new application program was being downloaded or after a configuration change. This is a safety feature designed to prevent unintended motor starts. The drive will not initiate operation until this preventative condition is safely resolved.

The thermistor input on an option board has detected an increase in motor temperature beyond safe limits, or the input itself is not properly terminated if unused. This indicates potential motor overload or inadequate motor cooling. Overheating can severely damage the motor windings, reduce motor lifespan, and lead to efficiency losses.

The 'Safe Disable' input on an OPTAF board has opened, activating a safety interlock that prevents drive operation. This feature is typically used to safely shut down or inhibit the start-up of the drive for maintenance or emergency situations. The drive will remain disabled until this safety condition is cleared.

The hardware-level overtemperature protection for the IGBT inverter bridge has activated, indicating an excessively high short-term overload current. This can be caused by heavy motor loading or an incorrectly sized motor. Persistent high temperatures can permanently damage the IGBTs, leading to catastrophic drive failure.

The cooling fan of the AC drive failed to start when a run command was issued. This indicates a potential fan motor failure, wiring issue, or a problem with the drive's internal fan control circuit. Without proper cooling, the drive will quickly overheat and trip, potentially leading to damage to internal power components.

A message sent over the CAN bus was not acknowledged by another device on the network. This typically points to a communication issue, such as an incorrectly configured device, a disconnected bus, or a fault in the CAN network's physical layer. Loss of communication can prevent proper control and monitoring of the drive.

A problem has been detected within the drive's application software. This could be due to a programming error, corrupted application file, or an unexpected runtime condition. An application fault will prevent the drive from executing its programmed functions correctly or at all, disrupting machine operation.

There is an incompatibility or communication failure between the NXS Control Unit and the NXP Power Unit (or vice versa). This prevents the control unit from properly commanding the power unit, effectively rendering the drive inoperable. This is often caused by mismatched hardware components or internal communication bus issues.

An option board has been replaced with another board of the exact same type that was previously used in the same slot. The drive has recognized the replacement and still has the old parameter settings available. This is primarily an informational alarm, indicating the hardware change and that the drive is ready to use the previously stored settings.

An option board of the same type, which was previously used in the same slot, has been added to the drive. The drive recognizes the board and has its parameters available. This is primarily an informational alarm, indicating the drive is ready to use the previously stored settings for this specific board.

An option board has been removed from its slot, making the device unavailable to the drive. This indicates a configuration change where a previously installed board is no longer present. The drive needs to acknowledge this change to clear the fault status.

An unknown or unrecognized power unit or option board has been connected to the drive. This indicates an incompatible hardware component that the drive cannot identify or operate with. The drive will be unable to start or function properly until a compatible device is installed.

The IGBT Inverter Bridge overtemperature protection has activated, detecting excessively high short-term overload current. This can be caused by heavy motor loading or an incorrectly sized motor. Persistent high temperatures can permanently damage the IGBTs, leading to catastrophic drive failure.

The brake resistor overtemperature protection has activated, indicating that the brake resistor is dissipating too much energy, likely due to overly heavy or frequent braking cycles. This condition can lead to premature resistor failure or a fire hazard if not addressed.

A problem has been detected with the encoder signals, such as missing channels (A or B), reversed direction, or a missing encoder board. This prevents accurate motor speed and position feedback, leading to unstable or incorrect motor control in closed-loop applications.

An option board or power unit has been replaced with a device of a different type or power rating. The drive detects this incompatibility and requires a complete reconfiguration. If parameters are not correctly reset and adjusted, the drive may operate incorrectly, become unstable, or fail to start.

A new option board of a different type has been added to the drive. The drive recognizes the new hardware but requires specific configuration to integrate it properly. Without correct parameter setup, the newly added option board may not function, or it could cause system instability.

A division by zero error has occurred within the custom application program running on the drive. This indicates a mathematical error in the program logic, which can cause the drive to halt or behave unpredictably. If left unaddressed, the drive cannot execute the affected part of the application, disrupting operations.

The analogue input configured for a 4-20 mA current loop is receiving a current signal below 4mA. This typically indicates a break or loose connection in the control cable, or a failure of the signal source device. Loss of the analogue signal means the drive cannot receive its intended reference or feedback, leading to incorrect control.

A digital input configured as an external fault has been triggered, indicating a fault condition in an external device connected to the drive. This causes the drive to trip, preventing further operation until the external fault is cleared. The specific external device must be identified and resolved.

Communication between the control panel (or NCDrive software) and the drive has failed. This is usually due to a defective physical connection or cable. Loss of keypad communication means the drive cannot be monitored or controlled locally via the control panel.

The data connection between the fieldbus master and the drive's fieldbus option board is defective, leading to a loss of communication. This prevents the drive from being controlled or monitored via the fieldbus network, disrupting integrated system operations. An incorrect installation or a faulty fieldbus master are common causes.

A defective option board or a faulty slot within the drive has been detected. This indicates a hardware failure preventing the option board from functioning correctly or being recognized by the drive. This fault will impact any functionality associated with the affected option board.

An internal temperature sensor has registered a temperature exceeding its predefined limit, or the sensor itself is disconnected or short-circuited. This indicates inadequate cooling, excessive load, or a sensor malfunction. Overheating can lead to premature component failure and severe damage to the drive.

The motor identification run, which is crucial for tuning the drive to the motor's specific electrical characteristics, has failed. This can occur if the run command was removed prematurely, the motor is not correctly connected to the AC drive, or an external load is present on the motor shaft during the process. An unsuccessful identification run can lead to suboptimal motor control and performance.

The actual status feedback from the mechanical brake (e.g., open/closed) does not match the drive's control signal for the brake. This indicates a malfunction in the brake mechanism, its feedback sensor, or the associated wiring. A malfunctioning brake poses a safety risk and can prevent proper machine operation or holding.

Communication has been lost between the Master and Follower drives via the SystemBus or CAN communication link. This could be due to incorrect option board parameters or a damaged/disconnected communication cable (optical fibre or CAN). Loss of communication prevents synchronized operation in a master-follower system, leading to operational halts.

The coolant circulation system for a liquid-cooled drive has failed. This means the drive is not receiving adequate cooling, which will rapidly lead to overtemperature conditions and potential severe damage to internal components. This requires immediate attention to the external cooling system.

The motor's actual speed deviates significantly from its commanded speed reference. This can be caused by a faulty encoder connection (if an encoder is used), or for Permanent Magnet Synchronous (PMS) motors, exceeding the pull-out torque. An uncorrected speed error leads to inaccurate motor control, poor process performance, and potential instability.

The 'Run Enable' signal, which is required for the drive to operate, is currently low or inactive. This is a safety interlock designed to prevent the drive from starting. The drive will remain disabled until the run enable condition is met and the corresponding signal is active.

An emergency stop command has been received by the drive from either a digital input or via the fieldbus, resulting in an immediate halt of operation. This is a critical safety function that stops the machinery in an emergency. The drive will not accept a new run command until the fault is reset and the emergency stop condition is completely cleared.

The main input power switch for the drive is detected as open, preventing power from reaching the drive and making it inoperable. This could refer to a physical disconnect switch, a tripped circuit breaker, or an internal contactor. The drive cannot function without incoming power.

An internal temperature sensor has registered a temperature exceeding its predefined limit, or the sensor itself is disconnected or short-circuited. This indicates inadequate cooling, excessive load, or a sensor malfunction. Overheating can lead to premature component failure and severe damage to the drive.

In a Master-Follower configuration, this fault code is generated when one or more of the follower drives trip into a fault state. This indicates an underlying issue with a specific follower drive, which then propagates to the master. The master cannot resume normal operation until the root fault on the follower drive(s) is identified and resolved.

The drive has detected an abnormally high current in one of the output phases, exceeding a hardware trip limit of 4 times the nominal current (Ih). This indicates an immediate and severe electrical overload condition. If left unresolved, it can lead to component damage or system instability.

The DC-link voltage has surpassed the drive's protective limits (e.g., above 911 Vdc for a 500 Vac unit or 1200 Vdc for a 690 Vac unit). This can be a hardware trip or sustained overvoltage due to control supervision. Persistent overvoltage can damage power components and reduce drive lifespan.

The earth fault protection ensures that the sum of the output phase currents is not zero, indicating a current leakage to ground. This protection works in conjunction with overcurrent protection for high current earth faults. An unaddressed earth fault poses a significant safety hazard and can cause severe damage to the drive or motor.

The DC-link voltage has dropped below acceptable limits, potentially triggering an undervoltage control supervision (S3). This could be caused by a low supply voltage, an internal frequency converter fault, a broken input fuse, or an open external charge switch. Prolonged undervoltage can cause erratic drive behavior and component stress.

The drive has detected a missing input line phase, as indicated by phase supervision for both diode supply (S1) and active front end (S2). This means one or more incoming power phases are not present or severely degraded. Running with a missing phase can cause damage to the drive and connected equipment.

The current measurement system has detected an imbalance where one phase current is either missing or significantly different from the other phases. This indicates an issue with the power delivery to the motor. Operating with unbalanced phases can lead to motor overheating and drive component stress.

The heatsink temperature of the drive has fallen below an acceptable operating limit, specifically under –10°C. Operating at excessively low temperatures can affect the performance and lifespan of electronic components.

The heatsink temperature of the drive has exceeded its acceptable operating limits, triggering a fault. An overtemperature warning typically precedes the actual trip limit. Sustained high temperatures significantly reduce the lifespan of power semiconductors and other internal components.

An error has occurred with the EEPROM checksum, indicating a parameter save fault, faulty operation during data storage, or a component failure within the EEPROM memory. This can lead to incorrect drive configuration.

The values displayed on the internal counters of the drive are incorrect or corrupted. This affects the accuracy of operational data logging.

The drive's internal watchdog timer has detected an issue preventing normal microprocessor operation or startup. This can occur if the drive startup is prevented or a run request is active while a new application is being loaded. This fault indicates a critical internal control issue.

The drive's startup sequence has been prevented, possibly because a run request was active while a new application was being loaded. This is a safety measure to prevent unintended operation during critical configuration changes.

The thermistor input on the option board has detected an excessively high motor temperature. This fault can be caused by motor overheating or a broken thermistor cable. Continued operation with an overheated motor can lead to winding damage.

The IGBT Inverter Bridge over-temperature protection has activated due to an excessively high short-term overload current. This indicates the power semiconductors are being stressed beyond their safe operating limits. Repeated trips can degrade the IGBTs.

An option board of a different type has been added to the drive, causing the drive to load default parameters. This indicates a change in hardware configuration that requires re-parameterization.

The current at an analog input has dropped below the 4mA supervision limit. This typically indicates a failure in the signal source, a broken control cable, or a loose connection within the current loop circuitry. This means the drive is not receiving expected sensor feedback.

A digital input configured for external fault monitoring has been activated, signaling a fault condition from an external device or system. This is a generic fault triggered by an external safety or monitoring circuit.

The communication link between the control keypad (or NCDrive software) and the AC drive has been interrupted or broken. This prevents control and monitoring via the keypad interface.

The data connection between the fieldbus Master and the fieldbus option board installed in Slot D has been broken. This results in a loss of communication with the control system.

This fault indicates a problem with an option board or the slot it is installed in, suggesting either a defective board or an issue with the slot's electrical connection.

The temperature protection function for sensor board 1 has detected an issue, which could be an exceeded temperature limit, an unwired or non-functional sensor, or a short circuit in the sensor wiring (A1-A3 conditions). This compromises temperature monitoring.

For liquid-cooled units, this protection detects a failure in the cooling liquid circulation, typically via an external sensor connected to the Cooling Monitor digital input. It generates a warning when the drive is stopped and a fault (with a coast stop) when running. Continued operation without proper cooling will lead to severe overheating.

The Main Circuit Breaker (MCB) state is inconsistent with the drive's command. This includes scenarios where the MCB opens when commanded to close, closes when commanded to open, opens externally while the AFE unit is running, or is in a tripped state as reported by a digital input. This is a critical safety and operational fault.

The temperature protection function for sensor board 2 has detected an issue, which could be an exceeded temperature limit, an unwired or non-functional sensor, or a short circuit in the sensor wiring (A1-A3 conditions). This compromises temperature monitoring.

The data connection between the fieldbus Master and the fieldbus option board installed in Slot E has been broken. This results in a loss of communication with the control system.

The LCL (Line Commutated Inductor) temperature has reached its warning limit, indicating elevated temperatures within the input filter components. While currently a warning, it suggests conditions that could lead to an over-temperature fault if unaddressed.

The drive failed to reach the required DC voltage within the set charging time for the Main Circuit Breaker (MCB). This can be due to a non-operational charging circuit, a high load on the DC link during charging, or an insufficient supply voltage for the charging circuit. This prevents the drive from starting up properly.

This fault is triggered by a digital input fault, indicating a problem related to the main fuse. It's an external input signaling a main fuse issue. This could mean the main fuse has blown or its monitoring circuit has an error.

This fault is triggered by a digital input fault, signaling an issue with the auxiliary voltage supply. This suggests a problem with the external auxiliary power source or its monitoring.

This fault is triggered by a digital input, indicating that a safe stop command or condition has been activated from an external device. This is a critical safety interlock.

This fault is triggered by a digital input fault, indicating an insulation problem detected by an external monitoring device. This points to a potential electrical leakage somewhere in the system.

This fault is triggered by a digital input fault, indicating an issue with the earth switch. This suggests the earth switch may be in an incorrect state or its monitoring circuit has an error.

This fault is triggered by a digital input fault, signaling an excessively high ambient temperature detected by an external sensor. This indicates the operating environment is too hot for the drive.

This fault is triggered by a digital input fault, indicating an electrical leakage detected by an external monitoring device. This is a general leakage indication from an external system.