AL083 Fault in Delta ASDA-B2 Servo Drive

AL083 Servo Drive Outputs Excessive Current in the Delta ASDA-B2 Servo Drive indicates that the drive has detected abnormally high output current flowing through the motor output terminals (U, V, and W). The servo drive continuously monitors the output current to protect the power module and motor. If excessive current is detected due to wiring faults or abnormal electrical conditions, the drive immediately generates Alarm AL083 and disables the servo output.

This fault generally indicates a problem with the motor power cable, motor wiring, or analog signal grounding, rather than a failure of the encoder.

Possible Causes

• UVW motor power cable short circuit.
• Exposed motor cable conductors touching each other or ground.
• Damaged or worn motor cable insulation.
• Incorrect motor wiring sequence (U, V, W).
• Missing motor phase connection.
• Loose motor terminal connections.
• Incorrect motor installation.
• Analog signal ground (GND) connected to another signal ground.
• Electrical noise or analog signal interference.
• Damaged motor winding.
• Short circuit inside the motor.
• Faulty servo output stage.
• Internal power module (IGBT) failure.
• Incorrect cable routing causing interference.

Solutions

• Inspect the UVW motor power cable for damage.
• Replace the UVW cable if the insulation is damaged or conductors are exposed.
• Ensure no exposed metal conductors are touching each other or ground.
• Verify the correct U-V-W wiring sequence according to the Delta wiring diagram.
• Check for missing or loose motor phase connections.
• Tighten all motor power terminals.
• Inspect the motor winding for short circuits.
• Verify that the analog signal GND is not connected to other signal grounds.
• Route motor and signal cables separately to reduce electrical interference.
• Correct all wiring according to the Delta user manual (Chapter 3).
• Restart the servo drive after correcting the fault.
• Contact Delta technical support if the alarm persists.

Additional Information

The Delta ASDA-B2 Servo Drive continuously monitors the output current supplied to the servo motor.

Alarm AL083 is generated when the drive detects excessive output current that could damage the power module or motor.

According to Delta, the most common causes are:

• UVW motor cable short circuit.
• Incorrect motor wiring.
• Analog signal interference caused by improper grounding.

Delta recommends checking:

• The condition of the motor power cable.
• The U-V-W wiring sequence.
• Missing motor phases.
• Proper grounding of the analog signal GND.

The analog signal ground must not be connected to other signal grounds, as improper grounding may introduce electrical interference and abnormal drive operation.

Unlike a normal Overload Alarm, AL083 usually points to a wiring or electrical installation problem rather than excessive mechanical load.

Common Symptoms

• Servo drive displays AL083 Servo Drive Outputs Excessive Current.
• Servo output is disabled immediately.
• Motor fails to start.
• Alarm appears immediately after enabling the servo.
• Fault occurs during motor startup.
• High output current is detected.
• Motor vibrates or jerks instead of rotating normally.
• Drive repeatedly trips after reset.
• Abnormal motor wiring or cable damage is found.
• Alarm clears after correcting the wiring fault.

Recommended Troubleshooting Sequence

1. Turn OFF the servo drive power.
2. Inspect the UVW motor power cable.
3. Check for exposed or damaged conductors.
4. Verify the U-V-W wiring sequence.
5. Check for missing motor phases.
6. Tighten all motor terminals.
7. Inspect the motor winding for short circuits.
8. Verify that the analog signal GND is not connected to other signal grounds.
9. Separate power and signal cables to minimize electrical interference.
10. Rewire according to Chapter 3 of the Delta user manual.
11. Restore power and restart the servo drive.
12. Verify normal motor operation.
13. Monitor output current during testing.
14. Replace damaged cables if necessary.
15. Contact Delta technical support if the alarm persists.

Excessive Current Check Table

Check Point	Action
UVW motor cable	Inspect for damage or short circuits
Cable insulation	Replace if worn or exposed
U-V-W wiring	Verify correct phase sequence
Motor phase connections	Check for missing or loose phases
Motor terminals	Tighten all connections
Motor winding	Inspect for short circuits
Analog signal GND	Ensure it is not connected to other signal grounds
Cable routing	Separate power and signal wiring
Servo output	Verify normal current after repair
Delta technical support	Contact if the alarm remains after inspection

Preventive Maintenance Tips

• Inspect motor power cables regularly for insulation damage.
• Replace worn or damaged UVW cables immediately.
• Verify the U-V-W wiring sequence during installation and maintenance.
• Tighten motor terminals during scheduled inspections.
• Keep motor power cables separate from analog and control signal cables.
• Use proper grounding practices for analog signals.
• Avoid exposing motor cables to excessive vibration or abrasion.
• Periodically measure motor insulation resistance.
• Use only Delta-approved replacement cables and components.
• Record recurring AL083 alarms to assist long-term diagnostics.

Proper inspection of the UVW motor power cable, motor wiring, phase connections, analog signal grounding, and cable routing, along with eliminating short circuits and electrical interference, will help prevent recurring AL083 Servo Drive Outputs Excessive Current faults in Delta ASDA-B2 servo drives, ensuring reliable current control, effective protection of the power electronics, and dependable long-term operation of the servo system.