Yaskawa Sigma 3 Servo Drive

Yaskawa Sigma 3 Servo Drive Fault Codes:

Fault Code and Meaning	Cause and Remedy
A.020 Parameter Checksum Error 1	Cause: Control power supply lowered/unstable (ranged from 30 VAC to 60 VAC). Remedy: Correct the power supply, and set Fn005 to initialize the parameter. Cause: Power supply turned OFF while changing parameter setting. Remedy: Set Fn005 to initialize the parameter and input the parameter again. Cause: Number of parameter writes exceeded upper limit (e.g., changed every scan). Remedy: Replace the SERVOPACK. Cause: SERVOPACK EEPROM and related circuit are faulty. Remedy: Replace the SERVOPACK.
A.021 Parameter Format Error	Cause: Model number in software is old/incompatible with current parameters. Remedy: Replace the SERVOPACK or change parameter settings to be compatible with the model number in the software.
A.022 System Parameter Checksum Error 1	Cause: Control power supply lowered/unstable (ranged from 30 VAC to 60 VAC). Remedy: Correct the power supply, and set Fn005 to initialize the parameter. Cause: SERVOPACK EEPROM and related circuit are faulty. Remedy: Replace the SERVOPACK.
A.023 Parameter Password Error	Cause: A SERVOPACK board fault occurred. Remedy: Replace the SERVOPACK.
A.02A Parameter Checksum Error 2	Cause: Control power supply lowered/unstable (30-60 VAC). Remedy: Correct the power supply, and set Fn005 to initialize the parameter. Cause: Power turned OFF while changing parameter setting. Remedy: Set Fn005 to initialize the parameter and input the parameter again. Cause: Number of parameter writes exceeded upper limit. Remedy: Replace the SERVOPACK. Cause: SERVOPACK EEPROM and related circuit are faulty. Remedy: Replace the SERVOPACK.
A.02b System Parameter Checksum Error 2	Cause: Control power supply lowered/unstable (30-60 VAC). Remedy: Correct the power supply, and set Fn005 to initialize the parameter. Cause: SERVOPACK EEPROM and related circuit are faulty. Remedy: Replace the SERVOPACK.
A.030 Main Circuit Detector Error	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.040 Parameter Setting Error 1	Cause: Parameter is set out of range. Remedy: Set the parameter within the specified range. Cause: SERVOPACK EEPROM and related circuit are faulty. Remedy: Replace the SERVOPACK.
A.04A Parameter Setting Error 2	Cause: Parameter is set out of range. Remedy: Set the parameter within the specified range. Cause: SERVOPACK EEPROM and related circuit are faulty. Remedy: Replace the SERVOPACK.
A.041 Dividing Pulse Output Setting Error	Cause: PC dividing pulse set for Pn212 is out of range/does not satisfy conditions. Remedy: Set Pn212 to the correct value.
A.042 Multiple Parameter Combinations Exceeding Set Range	Cause: Speed of program JOB operation (Fn004) out of range due to gear ratio/motor change. Remedy: Reduce electronic gear ratio (Pn20E/Pn210). Cause: Speed of program JOB operation out of range by changing JOG movement speed (Pn533). Remedy: Increase program JOG movement speed (Pn533). Cause: Movement speed of advanced autotuning (F017) out of range. Remedy: Reduce electronic gear ratio (Pn20E/Pn210).
A.050 Combination Error	Cause: SERVOPACK and servomotor capacities do not correspond (Capacity ratio ≤ 1/4 or ≥ 4). Remedy: Select the proper combination of SERVOPACK and servomotor capacities. Cause: The parameter written in the encoder is incorrect. Remedy: Replace the servomotor (encoder). Cause: A SERVOPACK board fault occurred. Remedy: Replace the SERVOPACK.
A.100 Overcurrent (Heat Sink Overheated)	Cause: Overload alarm reset by turning OFF power too many times. Remedy: Change the method to reset the alarm. Cause: Faulty connection between SERVOPACK board and thermostat switch. Remedy: Replace the SERVOPACK. Cause: Connection between grounding and U, V, or W is incorrect/shorted. Remedy: Check and correct wiring; repair/replace servomotor cable. Cause: Short circuit between phase U, V, or W of the servomotor. Remedy: Repair or replace the servomotor cable/motor. Cause: Wiring of regenerative resistor is incorrect. Remedy: Check and correct the wiring. Cause: Fault in dynamic brake circuit or activated too frequently. Remedy: Replace SERVOPACK, reduce load/rotations, or reduce DB operation frequency. Cause: Ambient temperature too high or heat radiation blocked. Remedy: Ensure ambient temperature is 55°C or less; check panel ventilation. Cause: SERVOPACK fan or board fault. Remedy: Replace the SERVOPACK.
A.300 Regeneration Error Detected	Cause: A SERVOPACK board fault occurred. Remedy: Replace the SERVOPACK. Cause: Pn600 value incorrect or resistor not connected/wiring issue. Remedy: Connect external resistor or set Pn600 to “0”; correct wiring. Cause: Jumper between B2 and B3 removed (500W+ motors). Remedy: Correct the wiring. Cause: Regenerative energy excessive or transistor/sensor fault. Remedy: Replace resistor/SERVOPACK; reconsider load conditions.
A.320 Regenerative Overload	Cause: SERVOPACK board fault. Remedy: Replace the SERVOPACK. Cause: Power supply voltage is 270 V or more. Remedy: Correct the input voltage. Cause: Regenerative energy is excessive / regenerating state continued. Remedy: Select proper regenerative resistance capacity or reconsider load/operation conditions. Cause: Setting of Pn600 is smaller than external resistor capacity. Remedy: Correct the set value of parameter Pn600.
A.330 Main Circuit Wiring Error	Cause: A SERVOPACK board fault occurred. Remedy: Replace the SERVOPACK. Cause: Incorrect AC/DC power input mode settings. Remedy: For AC: Pn001.2=0. For DC: Pn001.2=1. Cause: Pn600 is set to 0 if regenerative resistance is disconnected. Remedy: Set Pn600 to 0.
A.400 Overvoltage	Cause: AC power voltage is 290 V or more / excessive voltage change. Remedy: The AC power voltage must be within the specified range. Cause: Motor speed high/load inertia excessive (insufficient regenerative capacity). Remedy: Check inertia/load specs; reconsider load and operation conditions. Cause: SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.410 Undervoltage	Cause: AC power supply voltage 120 V or less / large voltage drop. Remedy: Ensure AC power supply voltage is within specified range. Cause: Fuse blown, inrush resistor disconnected, or temporary power failure. Remedy: Replace SERVOPACK; check voltage; restart operation. Cause: Servomotor cable or motor shorts to ground. Remedy: Repair/replace cable or servomotor. Cause: SERVOPACK fault. Remedy: Replace the SERVOPACK.
A.510 Overspeed	Cause: Incorrect wiring order (phases U, V, W) or encoder wiring. Remedy: Correct servomotor/encoder wiring. Cause: Noise interference in encoder wiring. Remedy: Take measures against noise for the encoder wiring. Cause: Position/Speed reference input too large or gain incorrect. Remedy: Reduce reference value; correct reference input gain setting. Cause: SERVOPACK board fault. Remedy: Replace the SERVOPACK.
A.511 Dividing Pulse Output Overspeed	Cause: Output frequency of dividing pulse exceeds 1.6 MHz. Remedy: Lower the setting of the PG dividing pulse (Pn212) or reduce servomotor speed.
A.520 Vibration Alarm	Cause: Abnormal vibration was detected. Remedy: Reduce servomotor speed; reduce speed loop gain (Pn100).
A.710 Overload: Momentary Overload	Cause: SERVOPACK board fault occurred. Remedy: Replace the SERVOPACK. Cause: Servomotor wiring incorrect or connection faulty. Remedy: Correct the servomotor wiring.
A.720 Overload: Continuous Overload	Cause: Encoder or Servomotor wiring is incorrect or faulty. Starting torque or actual torque exceeds ratings/capacity. SERVOPACK fault occurred. Remedy: Correct the encoder and servomotor wiring. Reconsider the load and operation conditions. Reconsider the servomotor capacity. Replace the SERVOPACK.
A.730 Dynamic Brake Overload	Cause: The rotating energy at a DB stop exceeds the DB resistance capacity. A SERVOPACK board fault occurred. Remedy: Reduce the motor speed. Reduce the load moment of inertia. Reduce the number of times of the DB stop operation. Replace the SERVOPACK.
A.740 Overload of Surge Current Limit Resistor	Cause: The inrush current limit resistor operation frequency at main circuit power ON/OFF exceeds allowable range. A SERVOPACK board fault occurred. Remedy: Reduce the number of times that main circuit’s power supply is turned ON/OFF (5 times/min or less). Replace the SERVOPACK.
A.7A0 Heat Sink Overheated	Cause: The load exceeds the rated load. Ambient temperature exceeds 55°C. Overload alarm was reset too many times by power cycling. Incorrect connection of thermostat switch. Regenerative energy exceeds resistor capacity. Incorrect mounting (direction/distance) or poor heat radiation. SERVOPACK fan or board fault. Remedy: Reconsider load and operation conditions. Ensure ambient temperature is 55°C or less. Change the method to reset the alarm. Replace the SERVOPACK.
A.810 Encoder Backup Error	Cause: Absolute encoder used with incremental setting (or vice versa). Encoder cable was disconnected. Power not supplied from PG power supply or battery. Absolute encoder fault. SERVOPACK fault. Remedy: Replace the SERVOPACK (if board fault). Confirm connections and set up the encoder. Replace the battery or supply power to the encoder. If alarm cannot be reset by setup, replace the SERVOPACK.
A.820 Encoder Checksum Error	Cause: A fault occurred in the encoder detected by self-diagnosis. A SERVOPACK fault occurred. Remedy: Set up the encoder. If frequent, replace the servomotor. Replace the SERVOPACK.
A.830 Absolute Encoder Battery Error	Cause: Battery connection is incorrect. Battery voltage is lower than 2.7 V. SERVOPACK board fault. Remedy: Reconnect the battery. Replace the battery, then turn ON power to the encoder. Replace the SERVOPACK.
A.840 Encoder Data Error	Cause: Malfunction occurred in the encoder (noise, grounding, etc.). Encoder fault. SERVOPACK board fault. Remedy: Turn encoder power OFF/ON. If frequent, replace servomotor. Correct wiring (separate encoder cable from power lines, check grounding). Replace the SERVOPACK.
A.850 Encoder Overspeed	Cause: Servomotor runs at 200 RPM or more when power/SEN signal turns ON. Encoder fault. SERVOPACK board fault. Remedy: Turn ON encoder power when servomotor runs at less than 200 RPM. Replace the servomotor. Replace the SERVOPACK.
A.860 Encoder Overheated	Cause: Ambient temperature around servomotor is too high (>40°C). Servomotor load is greater than rated load. Encoder or SERVOPACK fault. Remedy: Ensure ambient temperature is 40°C or less. Ensure load is within specified range. Replace the servomotor or SERVOPACK.
A.870 Fully-closed Serial Encoder Checksum Alarm	Cause: Serial converter unit fault detected by self-diagnosis. SERVOPACK fault. Remedy: Set up the serial converter unit. If frequent, replace the unit. Replace the SERVOPACK.
A.880 Fully-closed Serial Encoder Data Alarm	Cause: Serial converter unit malfunctioned. SERVOPACK fault. Remedy: Turn power OFF and ON again. If frequent, replace the serial converter unit. Replace the SERVOPACK.
A.8A0 Fully-closed Serial Encoder Scale Error	Cause: A linear encoder fault occurred. Remedy: Replace the linear encoder.
A.8A1 Fully-closed Serial Encoder Module Error	Cause: A linear encoder fault occurred. A scale converter unit fault occurred. Remedy: Replace the linear encoder. Replace the serial converter unit.
A.8A2 Fully-closed Serial Encoder Sensor Error (Incremental)	Cause: A linear encoder fault occurred. Remedy: Replace the linear encoder.
A.b31 Current Detection Error 1	Cause: The current detection circuit for Phase U is faulty. Remedy: Replace the SERVOPACK.
A.b32 Current Detection Error 2	Cause: The current detection circuit for Phase V is faulty. Remedy: Replace the SERVOPACK.
A.b33 Current Detection Error 3	Cause: The detection circuit for the power supply is faulty. The servomotor cable is disconnected. Remedy: Replace the SERVOPACK. Check the motor wiring.
A.bF0 / A.bF1 / A.bF2 / A.bF3 / A.bF4 System Alarm 0-4	Cause: A SERVOPACK board fault occurred. Remedy: Replace the SERVOPACK.
A.C10 Servo Overrun Detected	Cause: SERVOPACK board fault. Order of Phase-U, -V, -W wiring is incorrect. Encoder fault. Remedy: Replace the SERVOPACK. Correct the servomotor wiring. Replace the servomotor.
A.C80 Absolute Encoder Clear Error and Multi-turn Limit Setting Error	Cause: An encoder fault occurred. A SERVOPACK board fault occurred. Remedy: Replace the servomotor. Replace the SERVOPACK.
A.C90 Encoder Communications Error	Cause: Encoder wiring or contact is incorrect. Noise interference due to incorrect cable specifications (non-twisted/unshielded). Wiring distance is too long (>20m). Remedy: Correct encoder wiring. Use tinned annealed copper twisted-pair shielded wire (core > 0.12mm²). Ensure wiring distance is 20m max.
A.C91 Encoder Communications Position Data Error	Cause: Noise interference (bent cable, damaged sheath). Encoder cable bundled with high-current lines. Floating Ground (FG) variance due to welder/machine influence. Remedy: Correct encoder cable layout. Separate encoder cable from high-current lines. Ground the machine separately from PG side FG.
A.C92 Encoder Communications Timer Error	Cause: Noise interference on the signal line. Excessive vibration/shocks applied to encoder. Encoder or SERVOPACK fault. Remedy: Take measures against noise for encoder wiring. Reduce machine vibration or mount servomotor securely. Replace the servomotor or SERVOPACK.
A.CA0 Encoder Parameter Error	Cause: An encoder fault occurred. A SERVOPACK board fault occurred. Remedy: Replace the servomotor. Replace the SERVOPACK.
A.Cb0 Encoder Echoback Error	Cause: Encoder wiring/contact incorrect. Noise interference (incorrect spec, long distance, bundled cables). Excessive vibration/shocks. Encoder or SERVOPACK fault. Remedy: Correct wiring (use twisted-pair shielded, max 20m). Separate from high-current lines. Ground machine separately. Reduce vibration. Replace servomotor or SERVOPACK.
A.CC0 Multi-turn Limit Disagreement	Cause: Parameter settings for SERVOPACK are incorrect. Multi-turn limit value not set or changed. SERVOPACK board fault. Remedy: Correct setting of Pn205 (0 to 65535). Execute Fn013 at alarm occurrence. Replace the SERVOPACK.
A.CF1 Fully-closed Serial Converter Unit Communications Error (Reception)	Cause: Wiring incorrect or faulty contact. Unspecified cable used. Cable too long (>20m). Cable sheath broken. Remedy: Correct cable wiring. Use the specified cable. Use 20m cable max. Replace the cable.
A.CF2 Fully-closed Serial Converter Unit Communications Error (Timer Stopped)	Cause: Noise interferes with cable between serial converter and SERVOPACK. Serial converter unit or SERVOPACK fault. Remedy: Correct wiring (separate signal line from power/grounding). Replace serial converter unit or SERVOPACK.
A.d00 Position Error Pulse Overflow	Cause: SERVOPACK board fault. Faulty contact or wiring in Servomotor U, V, W. SERVOPACK gain adjustment improper. Position reference pulse frequency too high. Parameter Pn520 setting incorrect. Load conditions (torque/inertia) exceed specifications. Remedy: Replace the SERVOPACK. Correct servomotor/encoder wiring. Increase speed loop gain (Pn100) and position loop gain (Pn102). Adjust pulse frequency, apply smoothing, or correct electronic gear ratio. Set Pn520 to proper value. Reconsider load and servomotor capacity.
A.d01 Position Error Pulse Overflow Alarm at Servo ON	Cause: Excessive position errors accumulated while the servo is OFF. Remedy: Do not run the servomotor in servo OFF status. Cause: With the setting not to clear the errors while the servo is OFF, the servomotor was running. Remedy: Make the setting so that the errors are cleared while the servo is OFF. Adjust the detection level.
A.d02 Position Error Pulse Overflow Alarm by Speed Limit at Servo ON	Cause: The servo turned ON with accumulated errors, and reference pulse was input during operation at the speed limit, therefore, the errors exceeded the Position Error Pulse Overflow Alarm Level (Pn520). Remedy: Do not run the servomotor in servo OFF status. Make the setting so that the errors are cleared while the servo is OFF. Correct the detection level. Adjust the speed limit level (Pn529) when servo turns ON.
A.d10 Motor-Load Position Error Pulse Overflow	Cause: Motor rotation direction and scale installation direction is opposite. Remedy: Install the scale in the opposite direction, or reverse the setting of fully-closed encoder usage method (Pn002.3). Cause: Position of the load such as stage and scale joint installation are incorrect. Remedy: Check the mechanical joint.
A.E00 COM Alarm 0	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.E01 COM Alarm 1	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.E02 COM Alarm 2	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.E07 COM Alarm 7	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.E40 MECHATROLINK II Transmission Cycle Setting Error	Cause: Setting of MECHATROLINK II transmission cycle is out of specifications range. Remedy: Set the transmission cycle to proper value.
A.E50 MECHATROLINK II Synchronization Error	Cause: WDT data of host controller was not updated correctly. Remedy: Update the WDT data at the host controller correctly. Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.E51 MECHATROLINK II Synchronization Failed	Cause: WDT data of host controller was not updated correctly at the synchronization communications start, and synchronization communications could not start. Remedy: Update the WDT data at the host controller correctly. Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.E60 MECHATROLINK II Communications Error	Cause: MECHATROLINK II wiring is incorrect. Remedy: Correct the MECHATROLINK II wiring. Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK. Cause: MECHATROLINK II data reception error occurred due to noise interference. Remedy: Take measures against noise. Check the MECHATROLINK II communications cable and FG wiring and take measures such as adding ferrite core on the MECHATROLINK II communications cable.
A.E61 MECHATROLINK II Transmission Cycle Error	Cause: MECHATROLINK II transmission cycle fluctuated. Remedy: Remove the cause of transmission cycle fluctuation at host controller. Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.EA0 DRV Alarm 0	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.EA1 DRV Alarm 1	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.EA2 DRV Alarm 2	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.ED0 Internal Command Error	Cause: Parameter was changed by the digital operator or the personal computer during MECHATROLINK II communications. Remedy: Stop changing parameter using digital operator and do not connect the personal computer during MECHATROLINK II communications. Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.F10 Power Line Open Phase	Cause: A SERVOPACK fault occurred (when control power turned ON). Remedy: Replace the SERVOPACK. Cause: The three-phase power supply wiring is incorrect. Remedy: Correct the power supply wiring. Cause: The three-phase power supply is unbalanced. Remedy: Balance the power supply by changing phases. Cause: The contact in three-phase power supply wiring is faulty. Remedy: Correct the power supply wiring.
CPF00 Digital Operator Transmission Error 1	Cause: The contact between the digital operator and the SERVOPACK is faulty. Remedy: Insert securely the connector, or replace the cable. Cause: The external noise interference occurred to the digital operator or cable is faulty (cable near noise source). Remedy: Do not lay the cable near noise source. Install digital operator far from noise source.
CPF01 Digital Operator Transmission Error 2	Cause: A digital operator fault occurred. Remedy: Replace the digital operator. Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.900 Position Error Pulse Overflow (Warning)	Cause: A SERVOPACK board fault occurred. Remedy: Replace the SERVOPACK. Cause: Wiring is incorrect or the contact of servomotor U, V, and W is faulty. Remedy: Correct the servomotor wiring. Correct the encoder wiring. Cause: The SERVOPACK gain adjustment is improper. Remedy: Increase the speed loop gain (Pn100) and position loop gain (Pn102). Cause: The position reference pulse frequency is too high. Remedy: Decrease slowly the position reference pulse frequency. Apply the smoothing function. Adjust the electronic gear ratio. Cause: Setting of the parameter Pn520 (Position Error Pulse Alarm Level) is improper. Remedy: Set the parameter Pn520 to a value other than “0”. Cause: The servomotor specifications do not meet the load conditions (torque, moment of inertia). Remedy: Reconsider and correct the load and servomotor capacity.
A.901 Position Error Pulse Overflow at Servo ON (Warning)	Cause: Errors accumulated excessively in servo OFF status. Remedy: Do not run the servomotor in servo OFF status. Cause: With the setting not to clear the errors while the servo is OFF, the servomotor was running. Remedy: Make the setting so that the errors are cleared in servo OFF status. Adjust the detection level.
A.910 Overload (Warning for alarms A710 and A720)	Cause: Wiring is incorrect and the contact in servomotor wiring is faulty. Remedy: Correct the servomotor wiring. Cause: Wiring is incorrect and the contact in encoder wiring is faulty. Remedy: Correct the encoder wiring. Cause: The starting torque exceeds the maximum torque. Remedy: Reconsider the load and operation conditions. Or, check the servomotor capacity. Cause: Temperature in the SERVOPACK panel is high. Remedy: Reduce the in-panel temperature to 55°C or less. Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK.
A.911 Vibration	Cause: Servo Amplifier gain is improper. Remedy: To adjust the gain, decrease the speed loop gain (Pn100) and position loop gain (Pn101), and increase the filter time constants such as torque reference filter (Pn401).
A.920 Regenerative Overload (Warning for alarm A320)	Cause: A SERVOPACK fault occurred. Remedy: Replace the SERVOPACK. Cause: Regenerative energy is excessive. Remedy: Check the regenerative resistor capacity, or reconsider the load and operation conditions. Cause: The setting of parameter Pn600 is smaller than the external regenerative resistor capacity. Remedy: Correct the setting of parameter Pn600.
A.930 Absolute Encoder Battery Warning	Cause: A SERVOPACK board fault occurred. (The absolute encoder is used in the incremental encoder setting.) Remedy: Replace the SERVOPACK. Cause: The battery connection is incorrect or faulty. Remedy: Connect correctly the battery. Cause: The battery voltage is lower than the specified value 2.7 V. Remedy: Replace the battery, and turn OFF the encoder power supply and ON again.
A.941 Change of Parameters Requires the Setting Validation	Cause: To validate new setting of this parameter, turn OFF the power and ON again. Remedy: Turn OFF the power and ON again.
A.94A Data Setting Warning 1	Cause: Disabled parameter number was used. Remedy: Use the correct parameter number.
A.94B Data Setting Warning 2	Cause: Attempted to send values outside the range to the command data. Remedy: Set the values within the range.
A.94C Data Setting Warning 3 (Calculation Error)	Cause: Calculation result of set value is incorrect. Remedy: Set the parameter within the range.
A.94D Data Setting Warning 4	Cause: Parameter size set in command is incorrect. Remedy: Use the correct parameter size.
A.95A Command Warning 1	Cause: Command sending condition is not satisfied. Remedy: Send a command after command sending condition is satisfied.
A.95B Command Warning 2	Cause: SERVOPACK received unsupported command. Remedy: Do not send an unsupported command.
A.95C Command Warning 3	Cause: MECHATROLINK II command cannot be executed due to parameter setting condition. Remedy: Set the parameter to execute the command.
A.95D Command Warning 4	Cause: Command sending condition for latch-related commands is not satisfied. Remedy: Send a command after command sending condition related to latch command is satisfied.
A.95E Command Warning 5	Cause: Subcommand sending condition is not satisfied. Remedy: Send a subcommand after command sending condition is satisfied.