Servo troubleshooting answers
18 questions with answers cited from the manufacturer manuals.
- 0Kinetix 5700 FLT S07 MTR OVERLOAD FL: what to check first?
The FLT S07 MTR OVERLOAD FL fault on an Allen-Bradley Kinetix 5700 servo drive indicates that the motor's thermal model has exceeded its factory-set thermal capacity limit. This fault often occurs after a demanding cycle…
- 0Kinetix 5700 FLT S43 FDBK LOSS FL: what to check first?
The FLT S43 FDBK LOSS FL fault on a Kinetix 5700 servo drive indicates that the detected voltage levels of the A/B channel signals from the feedback device fell below the factory limit. This fault applies to all compatib…
- 0Mitsubishi MR-J5 AL.052 after maintenance, what to check first?
The AL.052 alarm on a Mitsubishi MR-J5 servo amplifier indicates an excessive error, meaning the droop pulses exceeded the alarm occurrence level. This alarm can occur during acceleration, when an axis is blocked, or if …
- 0Mitsubishi MR-J5 AL.016 at power-up, what to check first?
Alarm AL.016 on a Mitsubishi MR-J5 servo amplifier indicates an Encoder initial communication error 1, meaning there's a communication issue between the encoder and the servo amplifier at power-up. This can occur after r…
- 0Mitsubishi MR-J4 AL.52: Error excessive after wiring work, what to check?
The AL.52 alarm on a Mitsubishi MR-J4 servo amplifier indicates an excessive following error, meaning the difference between the commanded and actual position has exceeded the alarm level. This often occurs during accele…
- 0Mitsubishi MR-J4 AL.51 during operation, what to check first?
The AL.51 Overload 2 alarm on a Mitsubishi MR-J4 servo amplifier indicates that the maximum output current flowed continuously. This typically happens during operation if the axis collides with an obstruction or the torq…
- 0Mitsubishi MR-J4 AL.50: Overload 1 during operation, motor turns poorly, what to check?
Alarm AL.50 on a Mitsubishi MR-J4 servo amplifier indicates Overload 1, meaning the load exceeded the amplifier's overload protection characteristic. If this occurs during operation and the motor turns poorly, it suggest…
- 0Mitsubishi MR-J4 AL.33 Overvoltage during deceleration, what to check?
The AL.33 Overvoltage alarm on a Mitsubishi MR-J4 servo amplifier indicates the DC bus voltage has exceeded its prescribed limit. When this fault occurs specifically during deceleration, it often points to an issue with …
- 0Mitsubishi MR-J4 AL.25: Absolute position erased after battery replacement, what to check?
The AL.25 alarm on a Mitsubishi MR-J4 servo amplifier indicates that the absolute position data has been erased or is faulty. This can occur after initial power-up in an absolute position detection system, or if the batt…
- 0Mitsubishi MR-J4 AL.20: Encoder normal communication error 1 while running, what to check?
The AL.20 alarm on a Mitsubishi MR-J4 servo amplifier indicates an encoder normal communication error 1, meaning an error occurred in the communication between the encoder and the servo amplifier after start-up. This typ…
- 0Mitsubishi MR-J4 AL.16: Encoder initial comm error 1, what to check first?
Alarm AL.16 on a Mitsubishi MR-J4 servo amplifier indicates an Encoder initial communication error 1. This means an error occurred during the initial communication between the encoder and the servo amplifier, typically a…
- 0Yaskawa Sigma-7 A.400 trips on deceleration, what to check?
An A.400 Overvoltage alarm on a Yaskawa Sigma-7 SERVOPACK indicates that the main circuit DC voltage is too high. If this alarm specifically occurs during deceleration, it points to issues related to regenerated energy. …
- 0Yaskawa Sigma-7 A.100 at servo ON, even unloaded: what to check first?
Alarm A.100 on a Yaskawa Σ-7 SERVOPACK indicates an overcurrent has flowed through the power transistor or the heat sink has overheated. This is a Gr.1 alarm and cannot be cleared with a simple reset. When it occurs imme…
- 0Yaskawa Sigma-7 A.d00 after rewiring, motor jerks: what to check?
The Yaskawa Sigma-7 SERVOPACK alarm A.d00, Position Deviation Overflow, indicates that the position deviation (following error) has exceeded the Pn520 setting. This often occurs during acceleration when the motor cannot …
- 0Yaskawa Sigma-7 A.810: Encoder Backup Alarm after motor replacement, what to check?
The A.810 Encoder Backup Alarm on a Yaskawa Sigma-7 SERVOPACK indicates that the absolute encoder has lost its position data due to a power supply failure. This alarm cannot be cleared with a standard alarm reset; the en…
- 0Yaskawa Sigma-7 A.720 after running for a while, what to check?
An A.720 alarm on a Yaskawa Sigma-7 SERVOPACK indicates a continuous overload, meaning the servomotor has been operating under a torque exceeding its rating for an extended period. This is a Gr.1 alarm and can be reset o…
- 0Yaskawa Sigma-7 A.710 after motor change, motor growls: what to check?
Alarm A.710 on a Yaskawa Sigma-7 SERVOPACK indicates an instantaneous overload, meaning the servomotor operated under a torque significantly exceeding its rating for a short period. This is a Gr.2 alarm and can be reset …
- 0Yaskawa Sigma-7 A.C90 at power-up, what to check first?
Alarm A.C90 on a Yaskawa Sigma-7 SERVOPACK indicates an Encoder Communications Error, meaning the SERVOPACK cannot communicate with the encoder. This is a Gr.1 alarm that requires the underlying cause to be resolved befo…