ABB ACS880

The encoder has detected an internal error related to its position counter. This indicates a problem with the encoder's ability to accurately track position, which can lead to inaccurate motor control or positioning if unresolved.

The encoder has detected an unspecified internal error. This signifies a general malfunction within the encoder hardware or firmware, compromising its functionality. Without resolution, motor control and feedback will be unreliable.

This event code is reserved and not actively used by the system for application events. Its appearance suggests that an unassigned event ID was triggered or a placeholder is being used inadvertently. Encountering this indicates a potential misconfiguration within the event generation logic.

The application event function block attempted to trigger an event ID that is not defined as a user-defined event. This typically means the event ID is outside the designated user-definable range (0xE100-0xE2FF) or has not been configured in the ApplicationParametersAndEvents tool.

The 'EventType' input for the application event function block has been set to an unsupported value. Valid types include Fault (1), Warning (2), and Pure (8). This error indicates an attempt to use an unrecognized event classification, preventing proper logging or processing.

The format or data type of the 'ID' input provided to the event function block is incorrect or incompatible with the expected event ID structure. This can occur if the ID is not a WORD data type or falls outside the expected hexadecimal range, leading to a failure in event registration.

Similar to 0x0001, this event code is reserved and currently not utilized by the system for specific application events. Its presence points to an event ID being triggered that is a placeholder or has no active definition. This could indicate a misconfigured event source.

The event system received a request to handle an event with an 'EventType' that it does not recognize. This is similar to 0x0003 but specifically indicates the system cannot categorize the event based on the provided type, leading to an unregistered event.

The system attempted to write a value to a parameter that is currently configured as write-protected. This prevents accidental or unauthorized changes to critical configuration settings. If left unresolved, the desired parameter change will not be applied.

The system attempted to access a parameter that is currently configured as hidden. This means the parameter is not visible through standard interfaces, potentially to simplify the user experience or restrict access. This prevents direct interaction with the parameter.

An operation was attempted on a parameter that is invalid for its type or current state, such as trying to assign a string value to a numeric parameter, or an incorrect parameter type is being used. This prevents data corruption or unexpected behavior within the drive.

An attempt was made to set a parameter's value below its defined minimum limit. This protects the system from invalid or unsafe operating points, ensuring operational stability. If the new value is absolutely required, the parameter limits must be adjusted first.

An attempt was made to set a parameter's value above its defined maximum limit. This prevents system operation outside safe or intended bounds, crucial for equipment longevity and safety. If the new value is critical, the parameter limits must be expanded.

The system attempted to select a value for a list-type parameter that is not available in its predefined list of options. This typically occurs when a discrete parameter is assigned an undefined enumeration value, leading to an invalid configuration.

The system attempted to access or modify a parameter using an invalid group or index. This means the specified parameter does not exist in the drive's parameter database, likely due to a typo or incorrect reference in the application code. This will prevent any operation on the intended parameter.

The drive's internal IGBT temperature has exceeded its safe operating limit, indicating potential overheating. This can lead to reduced lifespan or premature failure of the IGBTs if the root cause is not identified and resolved promptly.

An internal file read error has occurred within the drive. This means the drive cannot access critical internal files required for its operation, leading to a non-resettable fault. This could indicate corrupted internal storage or a hardware issue.

An internal error occurred while loading a data record within the drive. This suggests issues with internal data storage integrity or access, which is crucial for drive configuration and operational data. This fault can impact the drive's ability to maintain its settings or proper functionality.

The drive's application file is either incompatible with the current hardware/firmware or has become corrupted during storage or transfer. This critical fault prevents the application from loading and operating the drive, rendering it inoperable.

Loading of a user-defined parameter set failed. This can happen if the requested set does not exist, is incompatible with the control program's version, or if the drive lost power during the loading process. This prevents the drive from operating with the desired configuration, potentially defaulting to an unsafe or incorrect state.

An operating system error indicating that the drive's internal kernel (core operating system) is experiencing an overload. This is a severe internal fault preventing normal drive operation and cannot be reset by the user. It points to a critical issue with the drive's core processing capabilities.

The drive has encountered a conflict where a functionality requested by the PLC via Fieldbus Adapter A is either not available on the drive or has not been activated in its configuration. This prevents proper fieldbus control and data exchange, leading to communication errors or incorrect drive behavior.

A reference source is simultaneously connected to multiple parameters with different units, causing a configuration conflict. This inconsistency prevents correct signal processing and can lead to incorrect drive operation. Refer to warning A6DA for detailed information.

A mechanical brake control fault has occurred because the brake acknowledgment signal was not as expected during the brake closing sequence. This implies either the brake did not close, its feedback mechanism failed, or an obstruction is present, leaving the motor potentially unsecured or unable to hold position.

A mechanical brake control fault has occurred because the brake acknowledgment signal was not as expected during the brake opening sequence. This implies either the brake did not open, its feedback mechanism failed, or it is stuck, potentially preventing motor rotation or causing excessive load.

The conditions required for opening the mechanical brake cannot be met, often because the brake is being intentionally kept closed by a parameter setting (e.g., 44.11 Keep brake closed) or due to a safety interlock. This prevents motor operation and is usually a configuration or interlock issue.

The motor has not stopped within the maximum allowed time after an emergency stop command (Off1 or Off3 mode) was issued. This indicates a failure in the emergency braking sequence, which could lead to unsafe operation if the system cannot stop as expected. The drive trips and coasts to a stop.

An analog input signal is outside the limits specified for that input (under minimum or above maximum). This indicates a problem with the sensor, wiring, or the signal source itself. Incorrect analog input can lead to incorrect process control or drive operation.

A fault generated by the signal supervision 1 function, indicating that a monitored signal has violated its defined limits or conditions. This signifies an abnormal condition in a specific process signal that the drive is supervising. Unresolved, it can lead to incorrect operation or safety issues.

A fault generated by the signal supervision 2 function, indicating that a monitored signal has violated its defined limits or conditions. This signifies an abnormal condition in a specific process signal that the drive is supervising. Unresolved, it can lead to incorrect operation or safety issues.

A fault generated by the signal supervision 3 function, indicating that a monitored signal has violated its defined limits or conditions. This signifies an abnormal condition in a specific process signal that the drive is supervising. Unresolved, it can lead to incorrect operation or safety issues.

An attempt was made to access a parameter index that falls outside the permissible range for its group. This often happens with array-like parameters where indices are restricted to a specific count (e.g., Motor 1, Motor 2, but attempting to access Motor 3 if only 2 are supported).

An operation was attempted that would create an overlapping condition between parameter groups, which is not allowed by the system architecture. This can happen when configuring resources that are allocated in blocks, and a new allocation attempts to use an already occupied segment, leading to resource conflict.

This is a generic 'UFF error,' indicating an unspecified or internal error related to the User Function Flag system or a similar internal drive component. This often points to a software or firmware issue, or a complex interaction that is not explicitly covered by other error codes, potentially affecting drive functionality.

The drive trips on this fault when an earth fault or significant current unbalance is detected in the motor or motor cable. This indicates a severe insulation breakdown or a direct short to ground, posing a risk of equipment damage, electric shock, or fire.

The drive has detected a loss of one or more phases in the incoming supply power and has tripped. This fault prevents operation on an unbalanced supply which can cause severe damage to the drive's input rectifier stage and other internal components. It indicates a problem in the electrical supply chain.

The drive has detected an incorrect connection between the input power cables and the motor cables, specifically if the input power is connected to the motor output terminals. This is a critical wiring error that will trip the drive to prevent severe damage to the power unit and motor due to incorrect voltage application.

The drive has detected a loss of one or more phases in the motor's connection. This fault will trip the drive based on the setting in parameter 31.19 Motor phase loss to protect the motor from damage due to unbalanced currents. Running a motor with a phase loss can cause severe winding damage and overheating.

An external temperature sensor (either 1 or 2) connected to the drive has registered a temperature beyond its configured fault limit. This indicates a potential overheating condition in the monitored equipment (e.g., motor), risking damage if not addressed.

A main cooling fan fault has been detected in the inverter unit. This indicates a failure in the drive's primary cooling system. While other fans may compensate and switching frequency might be reduced, prolonged operation with a main fan fault risks overheating and damage to the drive.

An auxiliary fan fault has been detected; the auxiliary fan is not running. This compromises secondary cooling. The drive trips after a 2-minute suppression period during power-up, during which it only issues a warning. Continued operation without auxiliary cooling can lead to overheating.

A critical hardware failure has occurred within the Safe Torque Off (STO) circuit of the drive, compromising safety functionality. This means the drive cannot guarantee safe disconnection of motor torque, requiring specialist intervention to ensure safety integrity.

The Safe Torque Off (STO) function has been activated, meaning the motor's torque production is safely disabled. This usually results from a break in the external safety circuit connected to the XSTO connector or a diagnostic fault setting, preventing the motor from starting or running.

The memory within the drive's Power Unit has been cleared, indicating a loss of configuration or operational data. This internal fault requires expert diagnosis to restore functionality and prevent reoccurrence, as it affects the core logic of the power unit.

There is a discrepancy between the drive's physical hardware identification and the information stored in its memory unit. This often occurs after maintenance such as a firmware update or memory unit replacement, potentially preventing the drive from operating correctly or safely.

The feedback signal from the charging system is missing or not detected. This typically indicates a problem with the charging circuit or its monitoring, which could prevent the drive's DC bus from charging correctly, leading to operational failure or preventing the drive from starting.

An unidentified logical fault has occurred within the power unit. This suggests a deep internal problem with the power unit's control or processing, possibly due to corrupted firmware, a hardware malfunction, or an unexpected state. Unresolved, this prevents the drive from operating reliably and requires expert attention.

An internal software error has occurred within the drive's operating system or application. This is a critical fault indicating a software anomaly that prevents normal operation and usually requires expert intervention to resolve. This can be caused by corrupted memory or an unexpected program state.

The firmware installed on the control board is incompatible with the FPGA logic version on the power unit. This mismatch can occur after updates where one component was updated but the other was not, preventing proper communication and control between the two main drive components. This issue prevents the drive from operating.

A read error occurred with the mapping file for fieldbus adapter A. This file is essential for establishing proper data exchange between the drive and the PLC or control system via the fieldbus. Without a valid mapping file, fieldbus communication will fail, preventing remote control or monitoring.

An internal fault where the drive's processor is experiencing an overload of its internal tasks. This indicates a critical condition where the drive cannot maintain its real-time operations and cannot be reset normally. Continued operation is impossible and typically points to a fundamental software or hardware issue.

An internal fault indicating that the drive's program stack has overflowed its allocated memory. This is a severe internal software issue that prevents the drive from executing code correctly and cannot be reset by the user. It signifies a critical programming error or memory corruption.

An attempt to load or save drive parameters has failed. This could indicate an issue with internal memory, configuration storage, or a transient software problem during the parameter operation. This can lead to loss of configuration settings or prevent proper drive setup.

Communication has been lost on the embedded fieldbus (EFB). This means the drive is no longer receiving or sending data to the fieldbus master, leading to loss of control or monitoring via the fieldbus. Critical control functions may be disrupted.

The embedded fieldbus (EFB) configuration file could not be read by the drive. This prevents the EFB protocol from initializing correctly. The fieldbus communication will not function, and the drive cannot be controlled via EFB.

The embedded fieldbus (EFB) parameter settings are inconsistent or not compatible with the selected protocol. This prevents the EFB from operating correctly, leading to communication failure. Reviewing and correcting parameter settings is crucial.

The embedded fieldbus (EFB) protocol firmware could not be loaded, or there's a version mismatch between the EFB protocol firmware and the drive firmware. This means the EFB functionality is completely disabled. The drive cannot communicate via EFB.

An internal fault indicating an overflow in the text data buffer. This is an internal software or memory issue within the drive. If persistent, it suggests a deeper problem that could affect drive stability and operation.

An internal fault indicating an overflow in a 32-bit text table. This is an internal software or memory issue within the drive. If persistent, it suggests a deeper problem that could affect drive stability and operation.

An internal fault indicating an overflow specifically within a 64-bit text table in the drive's memory. This is a software anomaly where the allocated memory for a specific text data structure has been exceeded. Persistent occurrences indicate a software bug.

An internal fault indicating an overflow related to text files. This is an internal software or memory issue within the drive. If persistent, it suggests a deeper problem that could affect drive stability and operation.

Communication has failed between the drive and an installed option module (e.g., FEN-xx or FIO-xx), preventing proper control or feedback. This can lead to loss of specific functionalities controlled by the module, hindering system operation.

The control panel (or PC tool) has stopped communicating with the drive. This prevents operator interaction and monitoring through the panel. If communication is not restored, local control and diagnostics are unavailable. The auxiliary code specifies the I/O port affected.

The drive trips on this fault when communication to an I/O extension module fails. This is a critical communication failure that will halt drive operation, preventing proper control, command execution, and potentially causing significant process downtime.

An attempt was made to use a saved control panel reference in multiple control modes simultaneously, which is not permitted. The control panel reference can only be saved for one reference type at a time. This prevents correct reference assignment.

The motor has entered a stall condition, meaning it's unable to rotate due to excessive mechanical load or insufficient power from the drive. Prolonged stalling can lead to motor and drive overheating and damage if not quickly addressed.

The drive detects an issue with the brake resistor, indicating it might be disconnected, physically damaged, or improperly sized. This prevents proper dissipation of regenerative energy, potentially leading to DC bus overvoltage and drive trips during deceleration.

The brake resistor has overheated beyond its fault limit, indicating it's dissipating too much energy. This can be caused by continuous heavy braking cycles, improper resistor sizing, or inadequate cooling, posing a risk of resistor damage or fire.

A short circuit has been detected in the brake resistor wiring, or there's an issue with the brake chopper control circuit. This prevents the brake resistor from functioning correctly, leading to potential DC bus overvoltage and can damage the chopper or drive components.

A short circuit has occurred within the brake chopper's IGBT, indicating a component failure that disables the regenerative braking function. This prevents the dissipation of excess energy, potentially leading to DC bus overvoltage and further drive damage if not addressed.

The IGBT within the brake chopper has overheated beyond its internal fault limit, often due to high ambient temperatures, cooling fan failure, or excessive braking cycles. This fault protects the IGBT from permanent damage but requires investigation into the cooling system or operational demands.

No motor speed feedback signal is being received by the drive. This fault means the drive cannot accurately monitor motor speed, which is critical for closed-loop control and protection. The drive will likely trip or fail to start reliably, impacting performance and safety.

The motor is rotating at a speed exceeding its configured maximum allowed speed. This can be caused by incorrect speed limits, insufficient braking capacity, or changes in mechanical load under torque control. Uncontrolled overspeed can cause severe mechanical damage to the motor or connected machinery and poses a safety risk.

An internal fault has occurred within the encoder system itself, indicating a problem with the encoder's electronics or processing. This is a critical fault preventing accurate speed/position feedback, rendering closed-loop control impossible. This typically requires specialized assistance.

A feedback fault has occurred with Encoder 1. This can manifest during initial setup due to incorrect wiring, or after sustained operation due to damage, electromagnetic interference, or module failure. It results in a loss of accurate motor position/speed data, which is critical for precise motor control.

A feedback fault has occurred with Encoder 2. This is identical in nature to the Encoder 1 fault but pertains to the second encoder feedback channel, leading to similar loss of accurate motor position/speed data. This can affect dual-feedback systems or applications requiring redundant speed/position control.

The supply unit (LSU) did not become ready (e.g., main contactor/breaker closing) within the expected timeframe. This indicates a problem with the LSU's pre-charging or readiness sequence. The drive cannot operate without a ready supply unit.

The selected signal has fallen below the user underload curve, indicating an underload condition. This often means the motor is running without sufficient mechanical load or there's a problem with the process being controlled. Sustained underload can waste energy or indicate a process issue.

The selected signal has exceeded the user overload curve, indicating an overload condition. This often means the motor is under too much mechanical stress or there's a problem with the process being controlled. Sustained overload can lead to motor damage or premature wear.

A fault has occurred in an external device connected to the drive's external event input 1. This general fault indicates a critical issue with peripheral equipment that the drive is monitoring and requires immediate attention. The drive will trip to protect itself or the process.

A fault has occurred in an external device connected to the drive's external event input 2. This general fault indicates a critical issue with peripheral equipment that the drive is monitoring and requires immediate attention. The drive will trip to protect itself or the process.

The drive generates a warning when an earth fault or current unbalance is detected in the motor or motor cable. This indicates a potential insulation degradation or leakage current to ground, which requires investigation to prevent a full fault trip or safety hazard.

This warning is generated when the drive is stopped and either one or both Safe Torque Off (STO) signals are lost. It indicates that the STO function is active or improperly engaged, preventing the drive from starting, but not necessarily tripping if already stopped. This is a crucial indication of a safety circuit status.

The control panel (or connected PC tool) has lost communication with the drive. This prevents operator interaction and monitoring through the panel. If communication is not restored, local control and diagnostics are unavailable.

This warning is generated by a signal supervision function, indicating an abnormality or unexpected condition in a monitored signal, potentially due to out-of-range values, signal loss, or noise. This can affect the drive's control accuracy or lead to unexpected behavior.

This warning is generated because value counter 1 (also referred to as a value integrator) has reached its configured threshold. This indicates that an integrated value, such as accumulated energy or material flow, has accumulated to a set limit, potentially signaling a need for a process check or maintenance.

This warning is generated because value counter 2 (also referred to as a value integrator) has reached its configured threshold. This indicates that an integrated value, such as accumulated energy or material flow, has accumulated to a set limit, potentially signaling a need for a process check or maintenance.

This warning is generated by an on-time timer, signaling that a specific device requires cleaning based on its operational duration. An auxiliary code in the event log indicates which timer is responsible for triggering this warning. Ignoring this warning can lead to reduced efficiency, overheating, or premature failure of the device.

A main cooling fan fault has been detected in the inverter unit. This indicates a failure in the drive's primary cooling system. While other fans may compensate and switching frequency might be reduced, prolonged operation with a main fan fault risks overheating and damage to the drive. The drive generates a warning and attempts to continue operation.

An auxiliary fan fault has been detected; the auxiliary fan is not running. This compromises secondary cooling. During power-up, the drive only generates this warning for two minutes before potentially tripping if the fault persists. Continued operation without auxiliary cooling can lead to overheating.

No feedback has been received from the external motor fan. This indicates that the fan may not be operating, leading to potential motor overheating if cooling is insufficient. The drive may continue operation, but motor thermal protection could eventually trip it.

An error in temperature measurement from a KTY or PTC sensor connected to encoder interface FEN-xx has occurred. This could be due to incorrect parameter settings or using an unsupported sensor type (e.g., KTY on FEN-01). Inaccurate temperature feedback risks motor overheating or improper thermal protection.

The motor current is too high, indicating an overload condition on the motor. This can lead to motor overheating, winding damage, and reduced motor lifespan if sustained. The drive will eventually trip to protect the motor.

The brake resistor is either broken or not connected. This means the drive cannot dissipate regenerative energy, which can lead to overvoltage faults when decelerating or braking. The drive's ability to stop or manage energy is compromised.

The brake resistor temperature has exceeded the warning limit defined by parameter 43.12. This indicates the resistor is overheating, potentially due to excessive braking duty or improper dimensioning. Continued operation risks damage to the resistor or associated components.

One or more of the brake resistor data settings (parameters 43.08 … 43.10) are incorrect or missing. This prevents the drive from correctly calculating brake resistor operation and protection. Incorrect data can lead to improper braking or resistor damage.

The speed feedback configuration has changed or is inconsistent. The auxiliary code provides details on the specific encoder interface module and encoder affected, and the nature of the problem. This can lead to incorrect speed control or motor operation.

The drive generates a warning when communication to an I/O extension module fails. This indicates a disruption in the control signal flow between the drive and its peripheral I/O, potentially affecting system operation and control accuracy.

This warning is generated by an on-time timer or a value counter, likely indicating a scheduled maintenance alert for the motor bearings. It signals that a predefined operating threshold has been met, suggesting a need for inspection or service. Ignoring this could lead to bearing failure and motor damage.

This warning is triggered by an edge counter, implying a monitoring function for an output relay has reached a programmed limit or detected an unexpected edge transition. It likely indicates an issue with the relay's operation or a need for inspection. Unresolved, this could affect controlled equipment.

Warning generated by on-time timer 1, indicating that a predefined operational time limit has been reached or exceeded. This often serves as a maintenance reminder or an alert for extended operation. Failure to address could lead to component wear or overdue service.

Warning generated by on-time timer 2, indicating that a predefined operational time limit has been reached or exceeded. This often serves as a maintenance reminder or an alert for extended operation. Failure to address could lead to component wear or overdue service.

Warning generated by edge counter 1, indicating that a specific number of events (edges) has been detected or a threshold has been crossed. This is typically used for monitoring operations, component life, or sequence integrity. Ignoring this could lead to unexpected behavior or component failure if a limit is exceeded.

This warning is generated because edge counter 2 has reached its configured threshold. This indicates that a specific event or action monitored by this counter has occurred a set number of times, potentially signaling the end of a component's lifecycle or a need for inspection.

A fault has occurred in an external device connected to the drive's external event input 1. This general warning indicates an issue with peripheral equipment that the drive is monitoring. The drive continues to operate, but the external device needs attention.

A fault has occurred in an external device connected to the drive's external event input 2. This general warning indicates an issue with peripheral equipment that the drive is monitoring. The drive continues to operate, but the external device needs attention.

A fault has occurred in an external device connected to the drive's external event input 3. This general warning indicates an issue with peripheral equipment that the drive is monitoring. The drive continues to operate, but the external device needs attention.

A fault has occurred in an external device connected to the drive's external event input 4. This general warning indicates an issue with peripheral equipment that the drive is monitoring. The drive continues to operate, but the external device needs attention.

A fault has occurred in an external device connected to the drive's external event input 5. This general warning indicates an issue with peripheral equipment that the drive is monitoring. The drive continues to operate, but the external device needs attention.

The supply unit generates a warning when an earth fault or current unbalance is detected. This indicates a potential insulation issue within the supply unit's power circuit or its input cabling, requiring attention to prevent a full fault trip or damage.

The drive is entering sleep mode as part of its process PID control function. This is an informative warning, indicating normal operation when conditions allow for energy saving. It does not signify a fault requiring intervention.

DDCS (fiber optic) communication between converters (e.g., inverter unit and supply unit) has been lost. The inverter unit will continue operating based on the last received status, but synchronized operation and full diagnostics are compromised. Loss of communication can lead to system instability or incorrect power flow.

The supply unit (or another converter) has generated a warning. The auxiliary code specifies the original warning code from the supply unit's control program. This indicates a problem on the line-side of the system, which could affect the entire drive operation.

The speed controller autotune routine did not complete successfully. The auxiliary code provides details, such as the drive being stopped prematurely. This means the speed controller may not be optimally tuned, leading to suboptimal motor performance.

This alarm signal from the ground fault monitor (option +Q954) is explicitly recommended to be connected for immediate drive tripping upon detection of a ground fault in IT (ungrounded) systems. The contact is normally closed when no ground fault is present and has a load capacity of 250 V AC, 2 A. Be aware that the ground fault monitor performs self-testing, which might momentarily activate this signal, necessitating careful distinction between actual faults and test sequences.

This alarm signal from the ground fault monitor (option +Q954) is intended for general alarm indication purposes, rather than directly tripping the drive. The contact is normally closed when no ground fault is present and has a higher load capacity of 250 V AC, 8 A. It is crucial to understand that the monitor's internal self-testing might briefly activate this signal, requiring careful interpretation by any receiving alarm or monitoring system.

A resource failure has occurred on the I/O bus module. This means a critical component or allocated resource within the module (e.g., memory, processing units, communication channels) has become unavailable or corrupted, leading to operational issues and potential loss of I/O control.

A timeout occurred during an operation on the I/O bus module. This indicates that a communication or processing step did not complete within its expected timeframe, possibly due to bus congestion, a slow response from a connected device, or a module malfunction. This can lead to unresponsive I/O.

The type scaling process failed during PLC startup. This is a critical error that prevents the PLC from correctly interpreting data types and ranges for I/O and internal variables. It can halt the startup process, lead to incorrect calculations, and compromise process control.

The flash memory, specifically for the flash disk, has entered a temporary protected (read-only) 'panic mode'. This critical state is typically triggered to prevent further data corruption when severe integrity issues are detected, rendering the system unable to write data and potentially causing instability.

An error occurred while attempting to set a parameter for the I/O bus master. This indicates a problem with configuring the communication master, potentially preventing it from correctly initiating or controlling connected I/O devices. This can lead to a complete loss of I/O communication.

The display unit has an incompatible or incorrect firmware version installed. This mismatch can lead to the display not functioning, showing corrupted graphics, failing to communicate with the main processor, or displaying incorrect information. This hinders effective user interaction and diagnosis.

The CPU failed to set the 'Reboot at powerfail' parameter, which controls the system's behavior during power interruptions. This means the system might not restart correctly or automatically after a power failure, potentially requiring manual intervention to resume operation. This impacts system resilience.

The CPU has detected an unsupported or invalid combination of plugged option boards. This hardware configuration error can prevent the CPU from starting or operating correctly, as the system does not recognize the installed modules. This requires physical verification of the setup.

A restore operation on the CPU, likely involving configuration or application data, has failed. This can lead to the CPU operating with incorrect settings, an older configuration, or failing to start completely, compromising the intended system functionality. Data integrity is at risk.

An I/O bus module timed out during its initialization sequence. This critical error suggests a problem preventing the module from becoming ready for operation, possibly due to a hardware fault, firmware issue, or communication problem. The module will not be functional.

An I/O bus module failed to complete its reset sequence within the allotted time. This indicates a severe issue with the module's internal processing or its ability to respond to control signals, halting its operation and preventing it from becoming ready for use.

Communication has been completely lost with an I/O bus module, indicating a breakdown in the communication link. This critical failure means the module is no longer accessible or functional within the system, leading to a complete loss of I/O control for that module.

A severe error has occurred on the I/O bus module, significantly impacting its operation. More detailed information regarding the specific cause and context of this error is available in the system log files, which should be consulted for proper diagnosis and troubleshooting.

A severe, fatal error has occurred on the I/O bus module, leading to a critical system failure. This likely halts operation and requires immediate investigation into the system logs for specific details on the cause. Unresolved, this error will prevent the system from functioning.

A fatal error has occurred on the I/O bus module, causing the entire system to stop running. This indicates a critical fault that has rendered the system inoperable. Immediate intervention is required to identify and rectify the issue and restore system operation.

For an I/O bus module, the configured discrepancy time for a specific channel has expired. This typically occurs in safety applications where redundant signals do not match within the allowed time frame, indicating a potential sensor malfunction, wiring issue, or incorrect time setting. This can lead to safety shutdowns.

The flash disk medium has almost used its complete spare capacity or is already dead. This is a severe warning indicating imminent or actual storage failure, which can lead to irreversible data loss, system operational halts, and inability to store critical data. Immediate action is required.

A test pulse error has been detected on an I/O bus module channel. This indicates a problem during the module's self-diagnosis, where the generated test pulse or its response was unexpected, potentially due to wiring faults or sensor malfunctions. It can compromise the reliability of the I/O channel.

A test pulse cross-talk error has occurred on an I/O bus module channel. This suggests unwanted interference between adjacent channels or an issue where a test pulse is being incorrectly detected on another channel. This can lead to unreliable I/O operation, incorrect data, and system instability.

A general test error has been reported by an I/O bus module. This indicates a failure during an internal diagnostic test, implying an issue with the module's hardware or firmware functionality. This can lead to unreliable I/O behavior or a complete module failure.

An error occurred during the initialization process of the system's display unit. This means the display may not be functioning correctly, showing no output, or displaying garbled information, hindering user interaction, diagnosis, and overall system usability.

A 'stuck-at' error has been detected on an I/O bus module, indicating that a signal line or a logic gate within the module is permanently fixed at a high or low state. This prevents proper signal transmission or processing, leading to incorrect I/O values and unreliable control.

A cross-talk error has been detected on an I/O bus module. This means unwanted signal coupling is occurring between adjacent channels, leading to incorrect readings or control actions, and potentially compromising system integrity. This interference affects signal reliability.

The CPU failed to load the boot project because of an issue with loading retain data. This indicates that critical persistent data, necessary for the project's operation, could not be retrieved, potentially leading to an incomplete or incorrect system startup. This can cause the PLC to run with default or corrupted settings.

The CPU failed to load the boot project because the retain data detected does not match the project's requirements. This mismatch can occur after firmware updates or project changes, causing the CPU to reject the current configuration and potentially halting operation. Data consistency is crucial.

The CPU was unable to load the boot project because it detected insufficient licensing for the application. This prevents the application from starting and running, indicating a licensing issue rather than a hardware fault. The PLC may enter demo or stop mode, rendering it inoperable for licensed features.

The CPU failed to load the boot project for an unspecified reason. This general error indicates a problem during the loading process that could stem from various issues, including corrupted project files, transient hardware issues, or firmware problems. Further investigation is needed to pinpoint the cause.

A backup operation on the CPU, such as saving configuration or application data, has failed. This means recent changes may not be properly archived, putting critical data at risk in case of a system failure, power loss, or accidental deletion. Regular backups are crucial for system recovery.

The root partition of the flash disk has 1% or less free space remaining. This is a critical error indicating imminent disk space exhaustion, which can lead to system instability, crashes, inability to write logs, or update firmware. Urgent action is required to prevent system failure.

A general test error has been reported by an I/O bus module on a specific channel. This indicates a failure during an internal diagnostic test, implying an issue with the module's hardware or firmware functionality related to that particular channel. This can compromise the reliability of the affected I/O.

The measured value on an I/O bus module channel exceeds the configured tolerance window compared to an expected or redundant value. This indicates a potential sensor malfunction, wiring issue, or an incorrectly set tolerance. It can lead to false alarms or inaccurate process control.

A 'stuck-at' error has been detected on an I/O bus module for a specific channel. This indicates that a signal line or a logic gate within that channel is permanently fixed at a high or low state, preventing proper signal transmission or processing. This leads to incorrect I/O values.

A readback error has occurred on an I/O bus module. This means the value read back from an output or an internal register does not match the value that was commanded or expected. This indicates a potential hardware fault, wiring issue, or corrupted internal state, compromising output verification.

A cross-talk error has been detected on a specific channel of an I/O bus module. This means unwanted signal coupling is occurring between adjacent channels, leading to incorrect readings or control actions, and potentially compromising system integrity. This interference affects signal reliability.

A general test error has been reported by an I/O bus module on a specific channel. This indicates a failure during an internal diagnostic test, implying an issue with the module's hardware or firmware functionality related to that particular channel. This can compromise the reliability of the affected I/O.

A general internal error has occurred within a specific channel of the I/O bus module. This signifies an unspecified hardware or software fault within that particular channel, potentially halting its functionality or causing unreliable operation. This indicates a localized critical internal issue.

A general test error has been reported by an I/O bus module on a specific channel. This indicates a failure during an internal diagnostic test, implying an issue with the module's hardware or firmware functionality related to that particular channel. This can compromise the reliability of the affected I/O.

The I/O bus module has detected a communication protocol variant that is not supported. This indicates an incompatibility in communication standards between the module and other devices, preventing proper data exchange and potentially halting the module's operation. This is a configuration or firmware mismatch.

The I/O bus module failed to complete its maximum allowed wait run time. This indicates a significant delay in processing or a communication deadlock, potentially causing I/O operations to time out and impacting system responsiveness or control. It suggests a performance or communication bottleneck.

The F-Parameter configuration for the I/O bus module does not match the module's physical address switch value. This discrepancy indicates an incorrect setup, potentially leading to improper I/O operation, communication failures, and system instability. Incorrect configuration can halt module functionality.

An internal data interchange failure has occurred within the I/O bus module. This suggests a critical hardware malfunction or corruption within the module's internal communication pathways, preventing proper data exchange and rendering the module inoperable. It is a severe internal fault.

The I/O bus module has incompatible hardware and/or firmware versions. This mismatch can lead to unexpected behavior, functional limitations, or complete operational failure as components are not designed to work together, potentially causing system instability.

A general internal error has occurred within the I/O bus module. This signifies an unspecified hardware or software fault within the module itself, potentially halting its functionality, causing unreliable operation, or leading to system downtime. It indicates a critical internal issue.

The sensor voltage detected on the I/O bus module is below the acceptable threshold. This indicates a potential issue with the power supply to the connected sensors or a fault within the sensors themselves, leading to inaccurate readings or complete sensor malfunction and unreliable process control.

The system's battery is either empty or entirely missing. This warning indicates that non-volatile data, such as configuration parameters, retained variables, or real-time clock settings, may be lost during power cycles if the issue is not resolved. This can lead to system re-configuration needs on every restart.

The flash disk medium has utilized 80% of its total spare capacity. This is a warning that the flash storage is approaching its wear limit, which can lead to reduced performance, slower write operations, and eventual component failure if not addressed. Proactive measures are recommended.

The root partition of the flash disk has 15% or less free space remaining. This warning indicates that critical system operations may be impacted, potentially leading to instability, inability to store new logs, updates, or temporary files. Continued operation with low space can cause system crashes.

The I/O bus module's compensation channel is providing incorrect measurements or a false temperature reading. This can lead to inaccurate process control, improper compensation for sensor errors, or system instability, especially in temperature-sensitive applications. Untrustworthy data poses operational risks.

For analog input AI531, the measurement is incorrect due to an excessively high potential difference. For PWM output CD522, the duty cycle is operating outside its acceptable range. Both issues can lead to inaccurate control, component damage, or system instability, requiring immediate attention to prevent operational errors.

An I/O module has been removed from a hot swap terminal unit while the system was operational. This is typically a warning indicating a change in the I/O configuration. If unintentional, this can lead to incomplete I/O functionality or system errors related to the missing module.

An incorrect I/O module type has been plugged into a hot swap terminal unit, replacing the module that was originally expected. This module type mismatch can lead to configuration errors, prevent the system from operating correctly, and potentially damage the module or terminal unit.

Communication has been lost with an I/O module installed on a hot swap terminal unit. This indicates a failure in the communication link or a fault within the module itself, preventing data exchange and rendering the I/O module inoperable. This affects all connected sensors/actuators.

An I/O module that does not support hot swap functionality has been detected on a hot swap terminal unit. This configuration mismatch can lead to improper operation, module damage if removed/inserted while powered, or general system errors. Modules not designed for hot swap require specific handling.

The system requires a hot swap terminal unit for proper operation, but it was not detected or is missing. This configuration error can prevent the system from recognizing or communicating with I/O modules, leading to incomplete system functionality or a halt.

The hot swap terminal unit itself has been identified as defective. This hardware fault can prevent proper communication with any I/O modules connected to it, potentially leading to widespread I/O errors and system instability. All modules on this unit will be affected.

Communication with the hot swap terminal unit has been lost. This can be due to a temporary glitch or a hardware failure in the terminal unit or its communication path, affecting all I/O modules connected to it. This can lead to loss of I/O control.

An I/O bus module has been identified as not having passed its factory tests. This indicates a manufacturing defect or pre-existing hardware fault, which could lead to unreliable operation, premature failure, or incorrect functionality. This module is likely faulty out of the box.

The required process voltage (UP or UP3) for the I/O bus module is not present. This critical power supply issue will prevent the I/O module and any connected field devices from operating correctly, resulting in a complete loss of I/O functionality.

The CPU was unable to locate at least one required parameter during operation. This parameter error can prevent proper configuration or execution of CPU functions, potentially leading to system misbehavior, incomplete startup, or a halt in processing. It indicates a configuration or memory issue.

The CPU encountered an error while attempting to read the value of at least one parameter. This can signify data corruption, an inaccessible memory location, or a configuration issue, affecting the CPU's ability to operate as intended and potentially leading to incorrect processing or system failures.

Safe Torque Off (STO) signal 1 has been lost or is not correctly applied. This fault often occurs in conjunction with 5091 (if running) or A5A0 (if stopped) and signifies a problem with one leg of the dual-channel STO safety circuit. This compromise of the STO function prevents safe operation.

Safe Torque Off (STO) signal 2 has been lost or is not correctly applied. This fault often occurs in conjunction with 5091 (if running) or A5A0 (if stopped) and signifies a problem with the second leg of the dual-channel STO safety circuit. This compromise of the STO function prevents safe operation.