Vacon NX Liquid-Cooled

The AC drive has detected an excessively high current, exceeding 4 times the nominal current (4*IH), in the motor cables. This condition typically results from a sudden heavy increase in mechanical load, a short circuit within the motor cables, or the use of an unsuitable motor for the application. Subcode S1 indicates a hardware trip, while S3 points to current controller supervision.

The DC-link voltage has exceeded its predefined limits. This often occurs due to overly short deceleration times during motor stopping, or significant overvoltage spikes originating from the mains supply. For 400-500Vac mains, a fault trips at 911Vdc (warning at 860Vdc); for 500-690Vac mains, a fault trips at 1250Vdc (warning at 1150Vdc). Subcodes S1 (hardware trip) and S2 (overvoltage control supervision) provide additional diagnostic context.

The current measurement system has detected that the sum of the motor phase currents is not zero, indicating a leakage current to ground. This fault is most commonly caused by insulation failure in the motor cables or within the motor windings themselves.

The pre-set charging time for the DC-link, defined by parameter P.2.1.3 (MaxChargeTime, default 5 seconds), has been exceeded. Specifically, the DC voltage failed to rise above 40VDC within 1 second during the initial charging sequence.

The charging switch is detected as open despite a START command being issued to the drive. This indicates either a malfunction in the charging switch control mechanism or a failure of the component itself.

A stop signal has been received from an option board, indicating activation of the emergency stop circuit. This fault causes the drive to stop immediately.

This fault signifies a critical issue such as a defective internal component or a short-circuit/overload condition in the brake resistor. This fault cannot be reset from the keypad, requiring a power cycle of the drive. If occurring with Fault 1, it suggests a motor cable or motor issue.

A general system malfunction has occurred, typically indicating a component failure or faulty internal operation. Detailed subcodes in T.14 provide insight into the specific area of failure, including feedback issues (S1, S6), ASIC trip (S4), VaconBus disturbance (S5), power unit problems (S8-S11), or expander/option board issues (S12, S30-S48).

The DC-link voltage has decreased below the predefined limits. This is most often caused by an insufficient supply voltage, a component failure within the drive, a defective input fuse, or an external charge switch that is not properly closed. For 400-500Vac mains, a fault trips at 333Vdc (warning at 371Vdc); for 500-690Vac mains, a fault trips at 573Vdc (warning at 633Vdc). Subcodes S1 (DC-link too low during run), S2 (no data from power unit), and S3 (undervoltage control supervision) are available.

An external electronic monitoring relay has detected an undervoltage, incorrect phase sequence, or a phase failure in the input line. The minimum threshold values are 360Vac for 400-500Vac supply and 470Vac for 525-690Vac supply, with a 0.1-second response delay. Possible causes include a missing supply phase, a blown supply fuse, incorrect mains cabling, or a grid interruption. Subcodes S1 (phase supervision diode supply) and S2 (phase supervision active front end) are available.

This fault indicates a problem with the brake chopper system. Possible causes include the absence of a brake resistor, a broken or open-circuited brake resistor, or a failure of the brake chopper circuitry itself.

The power module heatsink temperature has fallen below –10°C. This indicates that the power module or its coolant agent is too cold, which can impact drive performance and potentially lead to condensation issues.

The power module heatsink temperature has exceeded 60°C (fault) or 55°C (warning). The circuit board temperature might also be over 85ºC (warning at 75ºC). Causes include insufficient coolant flow, high ambient temperature, cooling fan failure, excessive power module loading, or issues with the drive's thermal model parameters. Subcodes S1 (Overtemperature warning in unit, board or phases), S2 (Overtemperature in power board), S3 (Liquid flow), and S4 (Overtemperature on ASIC board or driver boards) provide further diagnostic insight.

The motor stall protection has tripped, indicating that the motor has either stopped or is operating at a very low speed while a run command is active and under mechanical load. This typically suggests an excessive mechanical load or a mechanical obstruction preventing motor rotation.

The AC drive's internal motor temperature model has detected that the motor is overheating. This condition typically arises when the motor is subjected to sustained overloading, causing its winding temperatures to rise beyond acceptable limits.

The motor underload protection has tripped, indicating that the motor is operating with significantly less mechanical load than anticipated or with no load at all while still receiving a run command. This can happen if the load detaches or if a process requiring power is disengaged.

This is a warning indicating an unbalance condition between power modules in paralleled drive units. Subcode S1 signifies current unbalance, while S2 indicates DC-Voltage unbalance, pointing to an uneven load or voltage distribution across the parallel modules.

An error has been detected during the checksum verification of data stored in the EEPROM memory. This can affect various data sets, including firmware interface variables (S1, S2), system powerdown variables (S3), system parameters (S4, S10), or application-defined powerdown variables (S5, S6), suggesting potential data corruption within the drive's non-volatile memory.

This fault indicates that the values displayed on the drive's internal counters are incorrect or corrupted. Consequently, any operational data such as run hours or energy consumption derived from these counters cannot be trusted.

A microprocessor watchdog fault indicates faulty operation or a component failure within the drive's control unit. Subcode S1 points to a CPU watchdog timer issue, while S2 indicates an ASIC reset.

The start-up of the drive has been prevented. Subcodes specify the reason: S1 for prevention of accidental start-up, S2 if the START command is active when returning to READY state after Safe Disable, or S30 if START is active after system/application software download or application change.

The thermistor input on the OPT-AF option board has detected an increase in the motor temperature. Subcode S1 indicates activation on the OPT-AF board, while S2 applies to special application contexts.

The Safe Disable inputs SD1 and SD2 have been activated via the OPT-AF option board.

The IGBT Inverter Bridge overtemperature protection circuit has detected an excessively high short-term overload current, leading to a hardware-level temperature fault.

The cooling fan is jammed or has failed, which prevents proper air circulation and heat dissipation for the drive's power modules. This can lead to inefficient cooling and subsequent overtemperature conditions.

A message sent on the CAN bus was not acknowledged by another device. This typically indicates a communication problem between devices on the bus.

A problem has been detected within the application software running on the drive.

The VACON NXS Control Unit is unable to control the VACON NXP Power Unit, or vice versa. This indicates an incompatibility or mismatch between the control and power units.

An option board or power unit has been changed, and a new device of the same type and rating has been detected. Subcodes S1-S5 specify the changed component: Control board, Control unit, Power board, Power unit, or Adapter board/slot.

An option board has been added to the drive. Subcodes S1, S4, S5 specify the added component: Control board, Control unit, or Adapter board/slot.

An option board has been physically removed from the drive.

An unknown option board or drive has been detected. Subcodes in T.14 provide further detail: S1 (Unknown device), S2 (Power1 not same type as Power2), S3 (NXS or NXP1 and star coupler incompatibility), S4 (Software and control unit incompatible), S5 (Old control board version).

The IGBT Inverter Bridge overtemperature protection has detected an excessively high short-term overload current, indicating a thermal stress condition.

Overtemperature has been detected in the brake resistor. Subcodes S1-S5 (BCU related) specify the issue: S1 (Internal brake chopper overtemp), S2 (Brake resistance too high), S3 (Brake resistance too low), S4 (Brake resistance not detected), or S5 (Brake resistance leakage/earth fault).

A problem has been detected in the encoder signals. Subcodes in T.14 specify the issue: S1 (Encoder 1 channel A missing), S2 (Encoder 1 channel B missing), S3 (Both encoder channels missing), S4 (Encoder reversed), S5 (Encoder board missing), S6 (Serial communication fault), S7 (Channel A/B mismatch), S8 (Resolver/Motor pole pair mismatch), or S9 (Missed start angle).

An option board or power unit has been changed, and a new device of a different type or rating than the previous one has been detected. Subcodes S1-S5 specify the changed component: Control board, Control unit, Power board, Power unit, or Adapter board/slot.

An option board of a different or incorrect type has been detected in a slot. This indicates a hardware configuration mismatch between the inserted board and the expected or previously configured type. Subcodes S1-S5 specify the board type (Control, Control unit, Power board, Power unit, Adapter board & slot).

A division by zero error has occurred within the custom application program running on the drive. This is a software-related fault, indicating a logical error in the programmed code.

The current at the analogue input, which is configured for a 4 to 20mA signal range, has dropped below 4mA. This fault is commonly caused by a broken or loose control cable in the current loop or a failure of the signal source providing the analogue input.

A digital input configured as an external fault has been triggered, signaling an external condition that requires the drive to fault. The specific external condition depends on the system integration and what device or sensor is connected to this input.

The communication link between the control keypad and the AC drive has been broken. This can be due to a faulty physical connection or a damaged keypad cable, preventing the keypad from sending or receiving data from the drive.

The data connection between the fieldbus Master and the fieldbus option board in the AC drive is broken. This prevents the drive from communicating with the fieldbus network, disrupting control and data exchange.

This fault indicates a problem with an option board itself or the slot it is inserted into. Potential causes include a defective option board, improper insertion, or physical damage to the slot on the control unit.

The temperature of the external input AC choke has exceeded 130°C (fault) or 110°C (warning), as measured by a PT100 thermistor, or the temperature limit values set for the PT100 board parameters have been exceeded. This indicates inadequate cooling for the choke or an issue with the PT100 measurement system.

The motor identification run has failed. This can occur if the run command was prematurely removed before the identification process completed, if the motor is not properly connected to the AC drive, or if there is a mechanical load on the motor shaft during the identification sequence which should be performed without load.

The actual physical status of the mechanical brake (e.g., engaged or disengaged) does not correspond to the control signal issued by the drive. This discrepancy suggests either a mechanical failure of the brake, an issue with its wiring, or a problem with the drive's brake control output.

The SystemBus or CAN communication link between the Master and Follower units in a multi-drive system is broken. This interruption prevents synchronized operation and data exchange between the connected drives.

The 'Cooling OK' digital input, typically used for liquid cooling feedback, has triggered this fault, indicating an issue with the cooling system status.

The actual motor speed is not equal to the commanded reference speed. For Permanent Magnet Synchronous (PMS) motors, this specifically indicates that the pull-out torque has been exceeded.

The run enable signal is currently low, preventing the drive from operating.

An emergency stop command has been received either from a digital input or via fieldbus, indicating the E-stop feedback has triggered the fault.

This fault indicates issues with the drive's main input supply. It can be triggered if the main input switch is open, or if the Main Circuit Breaker (MCB) feedback signal is missing after the settled time defined by parameter P2.4.6 (Breaker Ack Time) has elapsed.