14.10.2025 by Viktor Siebert
Our practical case with a Yaskawa servo motor SGMSH-30DCA6F-OY and what it reveals about marketplace trade
Why we are telling this story?
We regularly purchase servo drives as replacements for our industrial customers fast, reliable, documented. At the end of August 2025, a customer urgently needed a Yaskawa SGMSH‑30DCA6F‑OY. What initially looked like a routine purchase turned into a case study showing how easily, in marketplace trading, the impression of “new” and “stocked in Germany” can arise even though reality is more complex. We present our findings factually, with data and measurements, without blanket accusations so that procurement, QA, and production teams can make informed decisions.
The listing: Serious impression at first glance
We found the motor on the German eBay site, item number 136310508714. The listing was written in proper German, with professional images, item location: Germany, stated VAT and WEEE details, and a delivery time of 3–4 days. Everything looked like a straightforward B2B purchase.
The invisible click: Seller address in China
Only when you actively open the legal information about the seller (an additional click that many overlook) do you see the seller’s address in our case China. This is not automatically unlawful; however, it explains why details like “item location Germany” and “delivery time 3–4 days” do not always align in practice. For buyers who depend on planning reliability, this difference matters.
The timeline: Promised vs. actually delivered
- Ordered & paid: 29.08.2025
- Promised: 3–4 days delivery time
- Delivered: 10.09.2025 (that is, 12 calendar days)
The delay alone wouldn’t be a drama. Combined with the remaining findings, however, it produced an overall picture that we are sharing here transparently.
Initial inspection: External features and first measurements
In our workshop, the camera runs in such cases. Unboxing with timestamp, photo documentation, saving the listing page as PDF/A. The first look: highly polished drive shaft, the nameplate appears unusually fresh.
Then the routine: insulation measurement, winding resistances, run on the test bench. Electrically the motor behaved inconspicuously so far, so good.
Data versus data: Encoder vs. nameplate
The next step is standard for us: reading the device via Yaskawa software. The encoder reported a manufacture time of October 2006. The motor nameplate, however, stated year 2018. This discrepancy is not trivial: in modern drives, encoders are often the system’s “memory.” When encoder data and nameplate contradict each other, that is a serious indication of refurbishment, modification, or component replacement.
Teardown: The internals tell the truth
We fully disassembled the motor. Inside we found dirt traces, the ball bearings were clearly worn, and in several places there were signs of prior use that are not visible from the outside. Together with the strikingly new nameplate, a consistent picture emerged: a cosmetically refurbished legacy unit, technically functional, but obviously older than the nameplate suggests.
Why such cases are risky
In industrial plants, availability, safety, and planning reliability are what count. A refurbished motor can also run, but hidden wear (e.g., on bearings or seals), outdated encoders, or changed characteristics can lead to fault patterns that are not understood at first glance:
- Incorrect resolution/parameters ⇒ control issues and quality fluctuations
- Increased vibration/bearing noise ⇒ shortened service life
- Unexpected failures ⇒ downtime, rush procurement, additional costs
For production managers, the difference between “honestly refurbished used goods” and “old goods appearing as new” is not academic but mission‑critical.
Pattern in the market: “New,” “NOS,” “like new” but often just cosmetics
For some time now, we have observed a growing number of listings promising “new,” “NOS” (“New Old Stock”), “refurbished,” or “like new.” Behind them, not infrequently, lies 10–20+‑year‑old technology, sometimes from product lines that the manufacturer no longer produces. Packaging, labels, and photos look fresh; the hardware often is not.
Added to this is the transparency gap between item location and seller address: those who read only the prominently displayed location might assume EU warehousing; in the fine print, however, the actual company registration is abroad. That complicates returns, warranty, and the assessment of delivery times.
How to recognize “cosmetics instead of quality”
- Unnaturally fresh nameplate (typeface, adhesive edges, material) on an evidently old product line
- Over‑polished shaft/screws, subsequently overpainted housings
- Contradictory date or serial information (encoder vs. nameplate vs. documentation)
- “New in original packaging,” although the product line has been discontinued for years
- Missing defensible test protocols, evasive answers to detailed questions
- Item location in the EU, but seller address outside the EU (visible only via an additional click)
How we test professionally, our process:
We professionally handle the authenticity and condition verification of servo drives. Our approach is reproducible and documented:
- Securing the evidence: listing page as PDF/A, screenshots of location/seller details, communication log, shipping label, tracking.
- Electrical baseline test: insulation measurement (including test voltage & temperature), winding resistances per phase, optional high‑voltage test.
- Functional test on the test bench: current draw, temperature profile, running noise, vibration.
- Software read‑out: encoder/device data, serial numbers, if applicable build information, comparison with the nameplate and manufacturer documentation.
- Mechanical inspection: bearing condition, shaft and fit play, seals, connectors, possible non‑original parts.
- Teardown in case of suspicion: internal cleanliness, signs of refurbishment, component replacement.
- Dossier: photo sets, measurement protocols, test report, understandable for procurement, QA, and production.
Checklist for procurement (to take with you)
- Read out encoder/device and compare with the nameplate (date, SN, resolution)
- Actively open the seller address (legal information) and document it
- Verify WEEE registration & VAT ID; archive listing & chat as PDF/A
- Request a test protocol before purchase (insulation, resistances, run)
- Obtain a manufacturer statement on build year/compatibility
- If in doubt: have it professionally checked, or walk away
Reporting and reaction: Facts, not emotions
We documented and reported our case. The case processing was completed very quickly. Without commenting on the platform’s evaluation here, we note: careful self‑verification and clean documentation remain for now the most reliable tools for companies to protect themselves while constructively promoting greater transparency.
Formulating responsibly
We use words like “counterfeit” or “fraud” publicly only when they are clearly substantiated. In many cases, these are refurbished used goods that appear as new or nearly new. What matters is that buyers know the facts: year of manufacture, condition, originality, compatibility. This is exactly what we prepare neutrally.
What we want from platforms
- Clearer display of the seller address alongside the item location (without a “click into the fine print”)
- Standardized mandatory information on year of manufacture/first commissioning for “new,” “NOS,” and “refurbished”
- Traceable verification mechanisms for critical categories in B2B technical trade
- Binding test protocols as part of the listing documentation
What comes next, transparency as a principle
We will analyze further cases, prepare them anonymized, and share lessons learned. In parallel, we offer companies the option to have suspicious or critical drives independently verified. This way we avoid bad purchases, unplanned downtime, and safety risks, and strengthen fair competition.
Conclusion
Our Yaskawa case shows how quickly a listing that appears serious raises questions upon closer inspection: item location vs. seller address, encoder date 10/2006 vs. nameplate 2018, polished shaft, worn bearings. The motor ran, but functionality is not the same as reliability. For industrial applications, what counts is what is measurable and evidenced. That is exactly where we start: with methodology, documentation, and transparency.
About us
We are a team of drive and QA specialists. We verify servo drives for authenticity, condition, and suitability, technically sound, across manufacturers. Our reports are prepared so that procurement, quality assurance, and production can all work with them. If you have a suspected case or want certainty before purchase: contact us. We help save costs, time, and nerves, before a supposed bargain becomes a production risk.
nformation about the mentioned Servopack and Servomotor:
More information about our Yaskawa repairs can be found here.
📞 Feel free to contact us if you have any questions regarding your Yaskawa drive technology. Our experienced team is always ready to assist you.
Technical Specifications
| Parameter | Value |
|---|
| Model | SGMSH-30DCA6F-OY |
| Power | 3.0 kW |
| Rated torque | 9.8 N·m |
| Rated speed | 3,000 rpm |
| Maximum speed | 5,000 rpm |
| Rated current | 8.9 A |
| Rated voltage | 400 V AC |
| Insulation class | F |
| Cooling method | Totally enclosed, non-ventilated (TENV) |
| Encoder | 17-bit incremental (131,072 pulses/rev) |
| Weight | approx. 12 kg |
| Manufacturer | Yaskawa Electric Co., Ltd., Japan |
The Yaskawa SGMSH-30DCA6F-OY is a high-performance AC servo motor of the Sigma-II series. It is designed for precise motion control tasks in CNC machines, robotic systems, and general machine tools. The motor offers an excellent balance of torque, speed, and accuracy and is widely used as an axis or spindle drive in modern industrial equipment.
Operating Conditions
- Ambient temperature: 0 – +40 °C
- Relative humidity: ≤ 90 %, non-condensing
- Installation altitude: ≤ 1,000 m above sea level
- Storage: dry, dust-free, low vibration (≤ 0.5 G)
Typical Alarms and Faults (excerpt from Sigma II User’s Manual)
| Code | Alarm Name | Description | Cause | Corrective Action |
|---|
| A.02 | Parameter Breakdown | EEPROM data error | Memory fault | Power cycle and reload parameters |
| A.03 | Main Circuit Encoder Error | Power circuit data abnormal | Electronic fault | Check servo amplifier |
| A.05 | Motor / Amplifier Mismatch | Wrong motor-drive pairing | Incompatible types | Verify models |
| A.10 | Overcurrent / Overheat | Overcurrent or heat sink too hot | Overload, poor cooling | Check current and ventilation |
| A.30 | Regeneration Error | Regenerative circuit fault | Defective resistor | Measure or replace resistor |
| A.40 | Overvoltage | DC bus voltage too high | Power surge | Verify mains voltage |
| A.41 | Undervoltage | DC voltage too low | Supply drop | Check power feed |
| A.51 | Overspeed | Speed too high | Encoder fault | Recheck parameters |
| A.71 | Overload High | Temporary overload | Mechanical stiffness | Inspect axis |
| A.81 | Encoder Backup Error | Encoder supply interrupted | Dead battery | Replace battery |
| A.82 | Encoder Checksum Error | Checksum mismatch | Memory corruption | Replace encoder |
| A.83 | Encoder Battery Error | Battery voltage low | Depleted battery | Replace battery |
| A.C9 | Encoder Communication Error | No encoder-amplifier communication | Cable break | Check or replace cable |
| A.CA | Encoder Parameter Error | Encoder parameters invalid | Parameter mismatch | Adjust settings |
| A.d0 | Position Error Overflow | Excess position deviation | Mechanical jam or overload | Inspect axis movement |
Main Components and Assemblies
| Component | Designation / Code | Function | Notes |
|---|
| Stator | 3-phase winding (400 V) | Generates magnetic field for torque | Insulation class F |
| Rotor | Permanent-magnet rotor | Transfers torque to shaft | High-energy magnets |
| Encoder | UTSIH-B17CK (or compatible) | Position and speed feedback | 17-bit incremental |
| Bearings | Precision deep-groove ball bearings | Reduces friction and radial play | Replace during maintenance |
| Brake (optional) | Ogura SBR-112V-200B | Holding brake for axis control | 24 V DC supply |
| Shaft seal | Double-lip oil seal | Protects against dust and coolant | Inspect periodically |
| Connectors | Power & encoder connectors | Interface to SGDH servo pack | Observe pin coding |
| Housing | Black coated aluminum body | Protection and heat dissipation |
Summary
The Yaskawa SGMSH-30DCA6F-OY is a 3 kW, 400 V class servo motor of the Sigma II series, known for its high precision, reliability, and efficiency.
Typical fields of use include machine tools from Hurco, Hitachi Seiki, and Mori Seiki, as well as automation and robotic applications.
In combination with a Yaskawa SGDH-50DE-OY servo pack, it provides accurate motion control, linear torque behavior, and repeatable positioning.
For long-term, trouble-free operation, encoder data, nameplate information, and electrical test values should be checked regularly.
A correct match of motor, servo amplifier, and operating environment ensures maximum lifetime and process reliability.