ABB ACS800 Frequency Converter: Common Faults and Maintenance Skills

Introduction to ABB ACS800 Frequency Converter

ABB ACS800 series frequency converter is a high-performance, widely adaptable AC frequency converter with a wide range of applications, advanced technology, powerful starting torque, automatic start, flux optimization, reliability and stability, and humanization With its user interface and other advantages, it is widely used in various industrial fields, such as electric power, petrochemicals, metallurgy, building materials, etc. Can control various types of motors, including AC asynchronous motors, AC synchronous motors, DC brushless motors, etc.

Industrial Applications of the ACS800

The ABB ACS800 series is widely used across multiple industries:

• Power industry: Controls motor speeds in power plants, substations, and distribution systems.

• Petrochemical industry: Manages pumps and fans to boost productivity and quality.

• Metallurgical industry: Regulates rolling mills and continuous casting machines.

• Building materials: Optimizes kilns, mixers, and production lines for consistent output.

Common Faults in ABB ACS800 Frequency Converters

Even with its strong design, the ACS800 drive may experience faults during long-term use. Understanding these common issues helps prevent costly downtime.

1. Inverter module damage:

This is usually caused by motor or cable damage and faults in the drive circuit. After repairing the drive circuit, the module should be replaced if the drive waveform is in good condition. After replacing the drive board on-site, it is necessary to check the motor and connecting cables. The inverter can only be operated when no faults are found.

2. No display after power-up:

This is usually caused by damage to the switching power supply or damage to the soft charging circuit, resulting in no DC power in the DC circuit. This situation can also occur if the starting resistor is damaged or the operation panel is damaged.

3. Display overvoltage or undervoltage:

usually caused by input phase loss, circuit aging and moisture on the circuit board.

4. Display of overcurrent or ground short circuit:

usually due to damage to the current detection circuit. Such as Hall elements, op amp circuits, etc.

5. Power supply and drive board display overcurrent onstartup:

This is usually caused by damage to the drive circuit or inverter module.

6. Normal No-Load Output but Overload Under Load

The no-load output voltage is normal, but overload or overcurrent is displayed after loading: This is usually caused by improper parameter settings or aging of the drive circuit or module damage.

7. Environmental Causes

Failures caused by the external environment, such as working environment temperature, vibration, moisture, electromagnetic induction interference, power supply abnormalities, lightning strikes, induced lightning, vibration and noise, etc.

These faults may affect the normal operation of the inverter and require timely investigation and repair. Different solutions should be adopted for different faults. If it cannot be repaired by yourself, it is recommended to contact professional technicians for repair

Case Study: Real-World Troubleshooting Examples

Case 1: Over-Temperature Alarm in ACS800-01-0070-7

• Problem:The inverter frequently tripped due to overheating.
• Analysis:Heavy dust on the heatsink blocked heat dissipation.
• Solution:After cleaning the heatsink and restoring airflow, the inverter resumed normal operation.
• Lesson:Overheating often results from poor environmental maintenance rather than hardware failure. Keep the inverter clean, dry, and well-ventilated to prevent similar issues.

Case 2: Slow Motor Speed Under DCS Control

• Problem:Motor ran abnormally slow at 30Hz setpoint under DCS control.
• Analysis:Although wiring was normal, the inverter showed overcurrent due to an increased load.
• Solution:Adjusting the U/F curve to raise low-frequency voltage improved startup torque and eliminated the fault.
• Lesson:Fine-tuning control parameters can resolve performance issues without replacing components.

Routine Maintenance Tips for ABB Frequency Converters

Routine maintenance methods and precautions for frequency converters include:

Environmental and Visual Inspection

• Ensure proper ambient temperature and humidity.

• Avoid dust, moisture, and corrosive gases.

• Check for loose cables, damaged filters, or heat sink issues.

Electrical and Signal Checks

• Verify power supply stability and grounding.

• Listen for abnormal vibrations or noises during operation.

• Inspect input/output signals for proper communication.

Parameter and Performance Testing

• Confirm motor and control parameters are correctly set.

• Conduct periodic component performance tests.

• Replace aging or unstable components early.

Safety Precautions

• Always power off the system before maintenance.

• Discharge residual electricity before touching internal parts.

• Avoid plugging or unplugging cables while the system is active.

Conclusion

Routine maintenance of the ABB ACS800 frequency converter is essential for:

• Prolonging its service life

• Maintaining optimal performance

• Preventing unexpected downtime

• Reducing repair costs

By keeping the environment clean, monitoring parameters, and acting on small issues early, operators can ensure stable, efficient, and reliable inverter performance in any industrial application.