EN
TDR-S Transformer DC Resistance & Turns Ratio Integrated Tester
TDR-S Digital Intelligent Transformer DC Resistance & Turns Ratio Integrated Tester (10A Max Current) with 0.1μΩ Resolution, 0.05% Turns Ratio Accuracy, 4-Wire Kelvin Measurement, Auto Vector Group Identification, Automatic Temperature Conversion, for 10kV-110kV Power Transformer On-Site Test.
- Description
- Specifications
- Applications
- Advantages
- FAQ
- Recommended Products
Description
The TDR-S is a professional, field-optimized integrated transformer test instrumentexclusively designed for fast and accurate measurement of winding DC resistance, turns ratio, vector group and polarity of power transformers. It fully complies with DL/T 845.3-2019, DL/T 963-2005 and IEC 60076-1:2022 standards, adopting advanced 4-wire Kelvin measurement technology and high-speed digital sampling to eliminate lead resistance and contact resistance errors.
The instrument features an all-in-one integrated design that combines DC resistance test and turns ratio test functions into one unit. One-time wiring completes both tests without changing test leads, reducing test time by 60% compared to traditional separate instruments. Equipped with a 7-inch high-resolution color touch screen and intuitive graphical interface, it supports automatic vector group identification, copper/aluminum temperature conversion and three-phase unbalance rate calculation. With a built-in 7.4V/10Ah large-capacity lithium battery, it can work continuously for more than 8 hours without external power supply, making it ideal for remote on-site testing. Ideal for power company on-site maintenance, transformer factory outgoing inspection, third-party testing institution on-site acceptance and industrial enterprise transformer commissioning tests.
Specifications
| Parameter | Specification |
|---|---|
| DC Resistance Test | |
| Maximum Output Current | 10A |
| Current Gears | 1mA, 10mA, 100mA, 1A, 5A, 10A (auto/manual selection) |
| Measurement Range | 10A: 0.1μΩ – 2Ω5A: 1μΩ – 4Ω1A: 10μΩ – 20Ω100mA: 100μΩ – 200Ω10mA: 1mΩ – 2kΩ1mA: 10mΩ – 20kΩ |
| Resolution | 0.1μΩ |
| Accuracy | ±0.2% of reading ± 2 digits (full range) |
| Stabilization Time | ≤3 seconds |
| Turns Ratio Test | |
| Test Range | 0.9 – 10000 |
| Accuracy | ±0.05% of reading ± 2 digits (≤500), ±0.1% of reading ± 2 digits (500) |
| Supported Vector Groups | Dyn11, Yyn0, Yd11, YNd11, Yy0, Dd0, etc. (all common groups) |
| Polarity Test | Yes (automatic judgment) |
| Phase Sequence Test | Yes (automatic detection) |
| General Parameters | |
| Temperature Conversion | Copper (20℃/75℃), Aluminum (20℃/75℃) automatic conversion |
| Three-Phase Unbalance Calculation | Yes (automatic pass/fail judgment) |
| Display | 7-inch high-resolution color touch screen |
| Data Storage | 1000 groups (with time stamp, power-off protection) |
| Data Export | USB interface, PDF/Excel report generation |
| Power Supply | AC 220V±10%, 50Hz + built-in 7.4V/10Ah lithium battery |
| Battery Life | 8 hours continuous operation |
| Charging Time | ~4 hours (full charge) |
| Protection Functions | Back-EMF protection, Over-voltage, Over-current, Short-circuit, Reverse polarity, Ground detection |
| Dimensions (mm) | 360×290×170 (L×W×H) |
| Weight | ~6.5kg (including battery) |
| Operating Temperature | -10℃ ~ +50℃ |
| Operating Humidity | ≤90%RH (non-condensing) |
| Altitude | ≤2000m |
| Compliance | DL/T 845.3-2019, DL/T 963-2005, GB 50150-2016, IEC 60076-1:2022 |
Applications
Core Test Objects
- Power transformers: 10kV-110kV oil-immersed power transformers (up to 63MVA)
- Distribution transformers: 10kV/35kV oil-immersed and dry-type distribution transformers
- Special transformers: rectifier transformers, furnace transformers, traction transformers
- Instrument transformers: current transformers (CT) and voltage transformers (VT)
- Electric motors: stator and rotor winding DC resistance test
Typical Usage Scenarios
- Power companies: on-site preventive maintenance tests of substation transformers
- Transformer manufacturing plants: outgoing inspection and quality control
- Third-party testing institutions: on-site acceptance and compliance testing
- Industrial and mining enterprises: transformer commissioning and preventive maintenance
- Power plants: generator transformer and auxiliary transformer tests
- Technical schools and universities: teaching and demonstration experiments
Advantages
Compliance with International Standards
Fully meets DL/T 845.3-2019, DL/T 963-2005 and IEC 60076-1 standards → test results are globally recognized
One-Time Wiring Dual Test
Complete both DC resistance and turns ratio tests with one wiring → improves test efficiency by 60%, reduces labor cost and human error
High Precision Measurement
0.1μΩ resolution and ±0.05% turns ratio accuracy → detects minute resistance variations and turns ratio errors
Automatic Vector Group Identification
Automatically identifies all common transformer vector groups → eliminates manual judgment errors
Automatic Temperature & Unbalance Calculation
Automatically converts resistance to standard temperature and calculates three-phase unbalance rate → saves calculation time, ensures result accuracy
Portable & Long Battery Life
6.5kg lightweight design with 8-hour battery life → ideal for remote on-site testing without power supply
Comprehensive Safety Protection
Multiple protection layers + automatic back-EMF protection → maximum safety for operators and expensive test equipment
High Cost-Effectiveness
Replaces two separate instruments at the price of one → saves equipment investment cost
FAQ
Q: What is the difference between TDR-S and traditional separate DC resistance and turns ratio testers?
A: Traditional testing requires two separate instruments and multiple wiring operations, which is time-consuming and prone to human error. TDR-S integrates both functions into one instrument, completes both tests with one wiring, reduces test time by 60%, and saves equipment investment and transportation costs.
Q: What vector groups does TDR-S support?
A: It supports all common transformer vector groups including Dyn11, Yyn0, Yd11, YNd11, Yy0, Dd0, etc. It can automatically identify the vector group without manual setting.
Q: Does it support automatic temperature conversion?
A: Yes. It can automatically convert the measured resistance value at the test temperature to the standard temperature (20℃ or 75℃) according to the temperature coefficient of copper or aluminum, making it easy to compare test results with standard values.
Q: Can it test on-load tap-changing transformers?
A: Yes. It supports continuous test of all taps of on-load tap-changing transformers. You can directly switch taps during the test without discharging the transformer, which greatly improves test efficiency.
Q: How long does the battery last?
A: It has a built-in 7.4V/10Ah large-capacity lithium battery that can work continuously for more than 8 hours, which is sufficient for a full day of on-site testing.
