The SGDV-120A01A is a single-axis AC servo drive from Yaskawa’s Sigma-5 (Σ-V) series, widely used in CNC machines, robotic arms, and automated production lines. If your machine throws a servo alarm or the SGDV-120A01A shows signs of failure, this guide covers the specifications you need for verification, the failures we see most often in our repair lab, and how to get a replacement fast.
| Key Takeaways | Details |
|---|---|
| Model | Yaskawa SGDV-120A01A Sigma-5 Servopack |
| Control Interface | Pulse train / analog voltage reference |
| Common Failures | Overcurrent (A.71/A.72), undervoltage (A.410), fan failure |
| Replacement Paths | New, refurbished, or repair — all available from stock |
| Stock Status | Available at OUKE, tested, 48-hour global shipping |
What Is the SGDV-120A01A?
The SGDV-120A01A belongs to Yaskawa’s Sigma-5 servopack family. It is a Yaskawa single-axis servo amplifier designed to drive medium-power AC servo motors in precision motion systems.
The model code breaks down as follows:
- SGDV — Sigma-5 series servopack
- A — 200 V class input
- 01 — Pulse train / analog voltage command input
- A — Standard model with base-mounted cooling
In our parts inventory, the SGDV-120A01A is one of the most requested Yaskawa Sigma 5 drives. Maintenance teams use it in CNC lathes, milling centers, and pick-and-place systems where 1.0–1.5 kW servo power is the sweet spot.
SGDV-120A01A Technical Specifications
| Parameter | Value |
|---|---|
| Series | Yaskawa Sigma-5 (Σ-V) |
| Type | Single-axis AC servo amplifier |
| Control Input | Pulse train / analog voltage reference |
| Feedback | Serial encoder (compatible with Sigma-5 motors) |
| Cooling Method | Forced air cooling (built-in fan) |
| Enclosure Rating | IP20 |
| Mounting | Base-mount (chassis installation) |
When you verify a replacement, match the rated current and control interface first. A drive with the wrong command input will not communicate with your motion controller without rewiring or parameter changes.
Common Failures of the SGDV-120A01A
In our repair lab, we see Sigma-5 servopacks every week. The SGDV-120A01A shares the same failure patterns as other drives in the 200 V class, but the 12 A output stage has its own weak points. Here are the five most common issues:
| Alarm Code | Fault Description | Probable Cause |
|---|---|---|
| A.71 | Overload (instantaneous) | Mechanical binding, wrong motor parameters, or damaged IGBT module |
| A.72 | Overload (continuous) | Oversized load, deteriorated motor bearings, or dusty heatsink |
| A.410 | Undervoltage | Input supply dip, loose terminal screws, or degraded DC bus capacitor |
| A.510 | Overspeed | Encoder noise, broken cable shield, or parameter mismatch |
| A.b31 | Current detection error | Internal current sensor fault or control board failure |
Beyond alarm codes, physical failures also occur:
- Cooling fan seizure — After 3–5 years, dust blocks the heatsink and the bearing seizes. Airflow stops, and the drive trips on A.72 within minutes.
- DC bus capacitor degradation — Capacitors lose capacitance. The drive starts normally but shuts down under load.
- IGBT module failure — Motor-side short circuits blow the output stage, producing A.71 and possibly damaging the motor.
Before scrapping the drive, check the alarm history on the front panel. The last five alarms reveal whether the root cause is electrical, mechanical, or environmental.
Need help reading the alarm? Our engineers have repaired hundreds of Sigma-5 drives. Send us the alarm code and machine model, and we will tell you whether the SGDV-120A01A is worth repairing or if a replacement is faster. Contact us at [email protected] or WhatsApp +86 15107352558.
Compatible and Replacement Options
If the SGDV-120A01A is obsolete or the repair turnaround is too long, you have three practical paths. Each has trade-offs in cost, delivery time, and compatibility risk.
| Option | Pros | Cons | Best For |
|---|---|---|---|
| New / Unused | Full warranty, longest life, no compatibility risk | Higher cost, long lead time if not in stock | Critical production lines with no tolerance for failure |
| Refurbished / Tested | Proven function, lower cost than new, faster delivery | Shorter remaining lifespan than new | Budget-conscious maintenance teams needing same-week delivery |
| Repair Existing Unit | Lowest cost, keeps same serial/parameters | Requires sending the unit in; not all failures are repairable | Drives with isolated faults (fan, capacitor, connector) |
When selecting a direct replacement, match the rated output current (12.0 A), control interface (pulse train / analog voltage), and input voltage class (200 V). A MECHATROLINK or EtherCAT variant will not drop in without controller-side changes.
If you are upgrading the entire axis, the Sigma-7 series (SGD7S) offers higher bandwidth, but it requires a matched Sigma-7 motor and may need controller reprogramming. For a direct SGDV-120A01A replacement, we recommend staying within the Sigma-5 family to avoid compatibility issues. At OUKE, we stock SGDV-120A01A units alongside other Yaskawa servo drives. Every unit is powered on, run through a basic function test, and packed for DHL shipment within 48 hours.
How do you choose between new, refurbished, and repair? If the machine is down now, order a replacement first and repair the failed unit later as a spare. If the alarm log shows only A.410, repair is usually cost-effective. If the IGBT is blown, replacement is safer. In our lab, about 60% of Sigma-5 drives have fixable faults; 40% need replacement.
FAQ
What motor pairs with the SGDV-120A01A?
The SGDV-120A01A is typically matched with Yaskawa Sigma-5 motors in the 1.0–1.5 kW range, such as the SGMJV or SGMAV series. Always confirm the motor nameplate current rating against the drive’s 12.0 A output.
Can I replace the SGDV-120A01A with a different Sigma-5 model?
Yes, but only if the replacement has the same current rating, voltage class, and control interface. A pulse-train model cannot replace an EtherCAT model without rewiring. Check the full model code before ordering.
Why does my SGDV-120A01A show alarm A.71 even with no load?
Alarm A.71 with no mechanical load usually points to an IGBT short, a damaged motor winding, or a bad encoder cable. Disconnect the motor cable and power cycle the drive. If A.71 appears immediately, the output stage is likely damaged.
How long does a Sigma-5 servopack typically last?
With clean power and proper cooling, a Sigma-5 drive can operate 8–10 years. Fan failure and capacitor aging are the most common age-related issues. Replacing the fan every 3–4 years extends service life significantly.
Does OUKE stock the SGDV-120A01A for immediate shipment?
Yes. We keep tested SGDV-120A01A units in our Dongguan warehouse. Orders ship within 48 hours via DHL or FedEx. No minimum order quantity. Contact [email protected] or WhatsApp +86 15107352558 for stock confirmation.
Get Your SGDV-120A01A Replacement Fast
When your SGDV-120A01A fails, every hour of downtime costs money. Whether you need a tested replacement unit, a repair evaluation, or help matching the right servo drive to your motor, OUKE can help.
We have 100,000+ automation parts in stock, including Yaskawa Sigma-5 and Sigma-7 servopacks. Every unit is function-tested before shipment. We ship within 48 hours to Europe, North America, Southeast Asia, and the Middle East. No MOQ.
Send your part number and alarm code to [email protected] or WhatsApp +86 15107352558 for a same-day quote.