29.09.2025 by Viktor Siebert
Repair Case Yaskawa Servopack SGDV-5R4D11A020000 with Error A.410 Undervoltage
Initial Condition.
The SGDV-5R4D11A020000 was sent in with error code A.410 Undervoltage.
The customer reported recurring production stops: the machine aborted sporadically, motors lost position, and workpieces were damaged.
A closer inspection revealed that the DC bus capacitor had already leaked electrolyte. This caused voltage drops in the DC bus, triggering alarm A.410. In addition, the leaked electrolyte had etched into the conductor tracks, leading to corrosion, interruptions, and partial short circuits.
Diagnosis & First Steps
After arrival, the drive was disassembled. Visual inspection confirmed:
- Electrolytic capacitors aged and partially leaked
- Corrosion on conductor tracks of the capacitor board
- Fan blocked by dust and oil deposits
A load test on the test bench was not possible, as the drive immediately went back into the undervoltage alarm.
Repair Process
- Complete Cleaning:
Boards were cleaned using special emulsion solution and ultrasonic treatment, then dried in the oven at 60 °C.
- Replacement of Critical Components:
- All electrolytic capacitors on boards 5R4DAA and 5R4ADB-020 replaced
- Damaged conductor tracks repaired by micro-soldering
- Fan replaced to prevent future thermal issues
- Preventive Replacement:
- Power semiconductors checked, thermally stressed components replaced
- Connectors cleaned and resoldered
- Electrical Testing:
- Insulation measurement of DC bus components
- Capacitance measurement of the new capacitors
- Load test on Yaskawa test bench (up to 1.5 kW load, simulation of rapid load changes)
- Final Testing:
- Endurance test over 8 hours with alternating torque profiles
- Monitoring of temperature, DC bus voltage, and output current
Result & Customer Benefit
The drive successfully passed all tests. The customer received a detailed test report.
Without timely repair, a total failure of the drive would have caused a shutdown of the entire production line.
The preventive renewal provided the customer with stable operation and a significantly extended service life.
Preventive Measures for the Customer
- Regular cleaning: Keep ventilation slots free, remove dust and oil deposits.
- Fan replacement: Every 3–5 years or when unusual noise occurs.
- Capacitor inspection: Check after 7–10 years and replace if capacity is reduced.
- Connectors: Regularly check for tight fit and corrosion.
- Insulation testing: Perform during machine maintenance.
- Seals: Check regularly in oil-contaminated environments.
Conclusion
The Yaskawa SGDV-5R4D11A020000 is a reliable servo amplifier for precision axis control.
This repair demonstrated the importance of preventive maintenance: capacitor and fan failures can be avoided if addressed early.
For the customer, the repair not only meant cost savings but also ensured production capability.
Information about the mentioned Servopack: Yaskawa Servopack SGDV-5R4D11A020000
Further details on our Yaskawa repairs can be found here: Yaskawa Sigma V Repair
📞 Feel free to contact us if you have any questions regarding your Yaskawa drive technology. Our team will be happy to assist you.
Device Specifications
| Feature | Value |
|---|
| Manufacturer | Yaskawa Electric Corporation |
| Model | SGDV-5R4D11A020000 |
| Series | Sigma V Servopack |
| Type | AC Servo Drive / Amplifier |
| AC Input | 3-phase 380–480 V, 50/60 Hz, 3.7 A |
| AC Output | 3-phase 0–480 V, 0–300 Hz, 5.4 A |
| Rated Power | 1.5 kW |
| Protection Class | IP10 |
| Ambient Temperature | 0–55 °C |
| Cooling | Heatsink with fan |
| Weight | approx. 3.5–4.5 kg |
| Dimensions | approx. 60 × 280 × 180 mm (W × H × D) |
| Compatible Motors | Yaskawa Sigma V AC Servo Motors |
| Control Interfaces | Digital and analog I/O, encoder feedback |
Application Environment & Compatible Devices
- Typical machines: Machine tools, automation cells, packaging machines, robotics and handling systems.
- Compatible controllers: Yaskawa Motion Controllers (MP series), compatible CNC controllers (Siemens, Mitsubishi with Yaskawa hardware).
- Compatible motors: Sigma V motors (e.g., SGMPH, SGMGH, SGMGV, SGMSV).
- Applications: Precision positioning, torque-controlled tasks, high-dynamic speed regulation.
Functional Description
The Yaskawa SGDV-5R4D11A020000 is a Sigma V servo amplifier designed for 1.5 kW motors.
Key functions:
- Control & feedback: Direct drive of AC servo motors with encoder feedback.
- Regulation: Precise position, torque and speed control.
- Safety & protection: Monitors over/under voltage, overcurrent, overheating, encoder and communication errors.
- Diagnostics & monitoring: Extensive alarms and warnings with easy integration into higher-level controllers.
- Communication: Optional feedback modules and fieldbus support.
Alarm Messages & Troubleshooting (Selection)
| Code | Description | Cause | Solution |
|---|
| A.100 | Overcurrent / heatsink overheat | Short circuit, overload, wiring issues | Check wiring, test motor/drive |
| A.300 | Regeneration error | Braking resistor missing or miswired | Connect/check resistor |
| A.320 | Regenerative overload | Excessive energy feedback | Adjust load/resistor |
| A.330 | Mains connection error | Wrong AC/DC wiring | Correct wiring/parameters |
| A.400 | DC bus overvoltage | Line voltage too high, inertia too high | Stabilize supply, adjust deceleration |
| A.410 | DC bus undervoltage | Voltage < 240 V at 400 V AC | Stabilize supply, check fuses |
| A.510 | Overspeed | Excessive reference, wiring error | Check parameters & wiring |
| A.520 | Vibration alarm | Resonances detected | Adjust speed/gain |
| A.710 | Overload high load | Motor heavily overloaded | Reduce load or upgrade motor |
| A.7AB | Fan failure | Internal fan blocked or defective | Clean or replace fan |
Components
| Name | PCB marking | Qty |
|---|
| Control board | SGDV-IFA11B | 1 |
| Capacitor board | 5R4DAA | 1 |
| Power board | 5R4ADB-020 | 1 |
| Power module | Power section | 1 |
| Heatsink & cooling fan | integrated | 1 |
| Connectors | Standard Yaskawa CN1A/B | – |