REXRTOH ECODRIVE DKC Series Drive Controller Comprehensive Fault Diagnosis and Maintenance Guide

F248- Low battery voltage: for motors with absolute value encoders. Its memory is backed up by batteries, and an alarm is triggered when the voltage drops below 2.8V. The battery design has a lifespan of approximately 10 years. When replacing the battery (part number: 257101), attention should be paid to operating it while the control power supply is not powered on, otherwise the absolute position will be lost and the "Set Absolute Measurement" command needs to be re executed.

F262- Status output external short circuit: The digital output channel of the driver has short circuit and overload protection. Short circuit (>350mA) or thermal overload (multi-channel>80mA) will trigger this error. Check the output circuit, eliminate short circuits, and ensure that the load current is within the rated range. Attention: Load with high impulse current, such as incandescent lamps, may be misjudged as a short circuit.

F276- Absolute Encoder Error: The deviation between the position stored during power-off and the position read by the encoder after power on exceeds the monitoring window defined by P-0-0097. It may be due to manual movement of the motor during initial power on or power off, or incorrect position initialization. Confirm the mechanical zero position and reset the absolute position if necessary.

F629/F630/F643/F644- Travel limit related errors: represent exceeding the software positive/negative limit and triggering the positive/negative limit switch, respectively. Triggered when the corresponding bit of parameter P-0-0090 is set to 'view limit as error'. The solution is to clear the error and only move the axis in the direction of the allowed work area.

F822- Motor encoder signal too small: The amplitude of the encoder signal exceeds the normal range (Uss 12.0V -18.0V). The reasons include feedback cable faults or damage to the encoder itself. This error can only be cleared in parametric mode and will cause the encoder simulation function to shut down.

F860- Power level overcurrent/short circuit: If the current exceeds twice the peak value, immediately turn off. The reason may be a short circuit in the motor cable, damage to the power part of the drive controller, or incorrect current loop parameters. It is necessary to check the cables, replace the controller, or restore the default parameters of the current loop.

F870-+24V control power supply error: The 24V control voltage exceeds the allowable tolerance (± 20%). Check and ensure that the 24V power supply is stable and not overloaded.

F878- Speed Loop Error: Triggered when current saturation, excessive speed error, and abnormal acceleration direction occur. Possible causes include incorrect motor cable connections, controller malfunctions, encoder malfunctions, or improper speed loop parameter settings.

Warning and Status Diagnosis: Key to Proactive Maintenance

Warning messages are valuable signals for proactive maintenance and preventing minor issues from escalating into major failures.

E209- Parameter Storage Activation: Indicates that the parameters are being saved. Do not turn off the power at this time, as it may result in parameter loss or damage.

E250/E251/E252- Overheating Warning: Temperature warnings for radiator, motor, and brake resistor respectively. A buffer time (such as about 30 seconds for the radiator) is provided before the final shutdown (F218/219/220), allowing the control system to execute a safe shutdown sequence (such as exiting the work area). At this time, the cooling conditions and load situation should be checked.

E254- Non return to zero: Appears when the absolute positioning command is issued but the axis has not executed the reference point return to zero. You must first perform a zero return operation or use a relative positioning command instead.

E260- Current Limit Activation: Indicates that the speed regulator has reached its output limit, limiting the driving acceleration capability and causing an increase in tracking error under position control. Need to reduce command acceleration/speed, or check if torque limit needs to be increased.

The status message intuitively reflects the working mode of the drive, such as A100 (torque mode), A101 (speed mode), A203 (position mode), AF (drive enable), JF/JB (positive/negative jog), etc. It is the basis for judging whether the drive responds to commands as expected.

Command diagnosis and advanced function execution

Command diagnostic messages track the execution process of specific control commands.

C100-C203 series: related to communication phase conversion and parameter checking. When switching from parameter mode to operation mode, if the parameters are found to be invalid, exceeded, or calculated incorrectly, the switch will be prevented and the corresponding C code will be prompted. Usually, it is necessary to connect to the DriveTop software and check and correct parameters in the 'Invalid Parameter List'.

C600 series - Drive control zeroing: covers various states and errors of zeroing commands, such as C601 (drive not enabled), C605 (zeroing speed too fast), etc. The correct zeroing requires matching hardware (reference switch, encoder zero pulse) and parameter settings (S-0-0041 zeroing speed).