External Fault (EF1)
+ Cause: The Inverter received abnormal input from external circuits.
+ Solution: Review the external circuits and sequence, and check the signal line of multi-function contact input for disconnection.

    Simultaneous Input of Forward and Reverse Rotation Commands
+ Cause: Forward and reverse rotation commands were simultaneously input for 0.5 second or more.
+ Solution: Review the sequence.

In case of any error, the ALARM indicator lights up, and the Inverter output is shut off, causing the motor to coast to a stop. To resolve the issue, check the cause of the error, take the necessary action, and perform a fault reset or turn the power off, then on.

    External Base Block in Progress (bb)
+ Cause: An external base block signal was input.
+ Solution: Make sure that the sequence circuit is appropriate.

Motor Overload (OL1)

- Cause: Motor overload protection function was activated by the electronic thermal relay due to potentially excessive load, improper V/f characteristics, short acceleration/deceleration time, or cycle time.

+ Solution: Review and adjust the load size, V/f characteristics, acceleration/deceleration time, and cycle time accordingly. Set the rated motor amperage in constant No. 31 to manage the electronic thermal reference current effectively. Adjusting the output voltage in the low-speed range to increase startup torque can lead to excessive voltage; decrease the setting of constant No. 30 (minimum output frequency voltage) if necessary.

Inverter Overload (OL2)

- Cause: Similar to motor overload, the Inverter overload protection function can be triggered by excessive load, improper V/f characteristics, or inadequate Inverter capacity.
+ Solution: Review the load size, V/f characteristics, acceleration/deceleration time, and cycle time. Consider the Inverter's capacity and ensure it is suitable for the load it is driving.

Additional Over-torque (OL3)

++ Extended Solution: For over-torque conditions, in addition to checking the n51 and n52 settings, it's crucial to understand the mechanical system's operation and address any issues causing excessive current flow. This might involve adjusting the load or mechanical components to ensure they are within the Inverter's operational limits.

Control Power Supply Fault (UV2) Reiteration

++ Extended Solution: If turning the power off and then on does not resolve the control power supply fault, it may indicate a more serious issue with the Inverter's internal power supply. Replacement of the unit might be necessary to prevent further damage or operational issues.

External Fault (EF1) Extended

    Additional Insight: When reviewing external circuits for an EF1 error, it's also important to ensure that all connections are secure and that there is no interference or short circuits in the external control signals. This can include inspecting for damaged cables or connectors that might be influencing the Inverter's operation.

Simultaneous Input of Forward and Reverse Rotation Commands Clarification

    Cause and Solution Expansion: This condition can cause significant stress on both the motor and the Inverter. To prevent it, ensure that the control logic is correctly designed to prevent simultaneous commands and that any programmable logic controller (PLC) or manual controls are properly sequenced.

Addressing Sequence Errors (SEr)

    Additional Context: Sequence errors typically indicate a conflict in the command sequence or an inappropriate change in operation mode (local/remote). Reviewing the entire control sequence for logical flaws or timing issues is critical. Ensuring that all commands are sent in an orderly and expected manner can prevent these errors.