Transformer Winding Deformation Tester (SFRA)
The SFRA Transformer Winding Deformation Tester is a cutting-edge diagnostic tool used to detect mechanical damage, distortion, or displacement in power transformers (66kV and above) caused by short circuits or transportation impacts.
Operated via Windows software, it utilizes Sweep Frequency Response Analysis to intelligently diagnose equipment health.
Product Overview
Internal mechanical deformation within a power transformer is a major hidden hazard that can cause sudden catastrophic failure.
This tester utilizes Sweep Frequency Response Analysis (SFRA) to map the amplitude-frequency response of transformer windings without the need to open the transformer tank.
By comparing frequency curves, it helps utility companies and maintenance engineers precisely identify mechanical integrity issues, strictly conforming to DL/T911-2016 and international IEC60076-18 standards.
Functions and Value:
1. Broad & Accurate Sweeping: Covers a wide sweep frequency range from 10Hz to 2MHz with an exceptional frequency accuracy of 0.001%, thanks to advanced digital frequency synthesis technology.
2. Ultra-Fast Testing Speed: Highly efficient data acquisition completes the standard frequency sweep for a single-phase winding in just 1 to 2 minutes, minimizing on-site outage time.
3. Intelligent Diagnosis Software: The Windows-compatible software automatically overlays up to 9 curves, calculating correlation coefficients across low, mid, and high-frequency bands to provide an instant, automated diagnostic conclusion (e.g., normal, slight, or severe deformation).
4. Ultimate Hardware Protection: Features built-in 5000V voltage isolation technology between the testing hardware and your PC, ensuring total safety for your connected laptop against accidental electrical surges.
5. High Dynamic Range: Delivers a vast measuring dynamic range of -120dB to 20dB, ensuring extreme sensitivity even when detecting minute displacements in massive power transformers.
6. One-Click Automated Reporting: The database seamlessly saves all historical test results. With just one click, it exports detailed diagnostic reports into MS Word or JPG picture formats.
Technical Details
| Parameter | Specification |
|---|---|
| Model | ZWRZ808A |
| Test Method | Sweep Frequency Response Analysis |
| Frequency Sweep Range | 10Hz - 2MHz |
| Frequency Accuracy | 0.001% |
| Output Voltage | Vpp-25V (Automatically adjusted) |
| Output / Input Impedance | 50 ohm / 1 Mohm |
| Measuring Dynamic Range | -120dB to 20dB |
| Testing Speed | 1 - 2 minutes per single-phase winding |
| PC Isolation Protection | 5000V electrical isolation |
| Software OS Compatibility | Windows 2000 / XP / 7 / 8 / 10 / 11 |
| Power Supply | AC 220V ±10%, 50/60Hz |
Model Selection Guide
| Feature | ZW5320 | ZW8320 |
|---|---|---|
| Max Output Current | 20A | 20A |
| Max Resistance Range | Up to 200Ω | Up to 25kΩ (Includes 10mA, <1mA steps) |
| 3-Phase Auto Test | Supported | Supported |
| Auto Degaussing | Supported | Supported |
| Magnetic Assist | Not available | Supported |
| Best Application | Standard distribution & medium power transformers. | Large power transformers requiring rapid LV winding tests. |
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Parts List
| Item NO. | Max Current | Measuring Range | Main Features | Recommended Application |
|---|---|---|---|---|
| GDZR-10A | 10A | 100μΩ - 20KΩ | Portable, built-in discharge alarm | Small to medium distribution transformers |
| GDZR-20A | 20A | 10μΩ - 10KΩ | High-speed testing, heat dissipation | Medium-sized power transformers |
| GDZR-40A | 40A | 1μΩ - 2KΩ | Dual-channel measurement, high current | Large-scale power transformers |
| GDZR-40A | Three-Phase 10A | 100μΩ - 10KΩ | Three-phase simultaneous measurement | Yn-type transformers, time-saving |
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Frequently Asked Questions
Contact our engineers for technical support and application guidance.
Power transformers can suffer from internal winding distortion or displacement due to short-circuit fault currents or physical impact during shipping. SFRA detects these invisible mechanical problems without opening the transformer tank, preventing unexpected failures.
Yes, the device and its analytical software are designed in strict accordance with the international standard IEC60076-18 and the Chinese power industry standard DL/T911-2016 for frequency response analysis on power transformers.
The software automatically groups the tested amplitude-frequency curves and calculates correlation coefficients (R values) across three distinct frequency bands (low, mid, and high). Based on these values, it intelligently outputs a conclusion: Normal, Slight, Obvious, or Severe Deformation.
Absolutely. The measurement unit incorporates 5000V high-voltage isolation technology at the PC connection interface. This prevents any accidental surges or interference from the transformer from traveling up the USB cable and damaging your computer.
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