EN
CPT-31 Current & Potential Transformer (CT/PT) Analyzer
CPT-31 Digital Intelligent Current & Potential Transformer Analyzer with Variable Frequency Volt-Ampere Test Technology, DSP+FPGA Dual-Core Architecture, 0.05% High Accuracy, for 10kV~500kV CT/PT Commissioning and Preventive Testing.
- Description
- Specifications
- Applications
- Advantages
- FAQ
- Recommended Products
Description
The CPT-31 is a professional-grade, all-in-one comprehensive transformer characteristic testerexclusively designed for testing and calibration of current transformers (CT) and potential transformers (PT) in 10kV~500kV power systems. It fully complies with IEC 60044-1/2/5/6, GB 1208-2006, GB 1207-2006 and DL/T 846.1-2016 standards, adopting advanced variable frequency volt-ampere test technology that eliminates the need for external current boosters or voltage boosters.
The instrument features an innovative DSP+FPGA dual-core architecture that ensures high-speed data acquisition and real-time signal processing. With 0.05% ultra-high ratio accuracy and support for testing protection CTs with knee voltages up to 45kV, it meets the test requirements of all types of measuring and protection transformers. Its unique one-click automatic test function automatically identifies transformer types, completes all test items in sequence, and generates standardized test reports with error curves and excitation curves.
Specifications
| Parameter | Specification |
|---|---|
| System Parameters | |
| Compliance Standard | IEC 60044-1/2/5/6, GB 1208-2006, GB 1207-2006, DL/T 846.1-2016 |
| Control Architecture | DSP + FPGA dual-core |
| Operating System | Embedded Linux |
| Display | 8-inch 1024×768 capacitive touch screen |
| Data Storage | >1000 groups test results |
| Data Export | USB 2.0 (JPG, PDF, Excel format) |
| Output Parameters | |
| AC Voltage Output | 0 ~ 180V, 0.1V resolution |
| AC Current Output | 0 ~ 10A, 1mA resolution |
| Output Power | 800VA maximum |
| Frequency Range | 1Hz ~ 100Hz (variable frequency test) |
| CT Test Parameters | |
| Ratio Range | 1 ~ 35000 |
| Ratio Accuracy | ±0.05% (1~2000), ±0.1% (2000~5000), ±0.2% (5000~35000) |
| Phase Accuracy | ±2 minutes |
| Maximum Knee Voltage | 45kV (tested at 5Hz) |
| Secondary Resistance | 0 ~ 8kΩ, ±0.2% accuracy |
| Secondary Burden | 0 ~ 160Ω, ±0.2% accuracy |
| Transient CT Test | TPS, TPX, TPY, TPZ supported |
| PT Test Parameters | |
| Ratio Range | 1 ~ 35000 |
| Ratio Accuracy | ±0.05% |
| Phase Accuracy | ±2 minutes |
| Secondary Resistance | 0 ~ 8kΩ, ±0.2% accuracy |
| Secondary Burden | 0 ~ 160Ω, ±0.2% accuracy |
| Power Supply | |
| External Power | AC 220V±10%, 50Hz |
| Built-in Battery | Lithium-ion battery, 11.1V/10000mAh |
| Battery Life | ≥4 hours continuous operation |
| Charging Time | ~3 hours (full charge) |
| Physical Parameters | |
| Dimensions | 400×300×160mm (L×W×H) |
| Weight | ~12kg (including battery) |
| Housing | Rugged engineering plastic |
| Protection Grade | IP54 |
| Operating Temperature | -10℃ ~ +50℃ |
| Storage Temperature | -20℃ ~ +60℃ |
| Humidity | ≤90% RH (non-condensing) |
Applications
Core Test Objects
- Current Transformers (CT): Measuring CTs (0.1~1.0 accuracy class) and protection CTs (5P, 10P, TPS, TPX, TPY, TPZ)
- Potential Transformers (PT): Inductive PTs and capacitive PTs (CVT)
- Other transformers: Current transformers for metering, voltage transformers for protection, combined transformers
Typical Usage Scenarios
- Power companies: Substation acceptance tests, transformer preventive maintenance, fault troubleshooting
- Power engineering companies: Transformer installation and commissioning, construction quality inspection
- Transformer manufacturers: Factory quality control, type tests, after-sales service
- Third-party testing institutions: Transformer calibration, performance testing, quality arbitration
- Industrial enterprises: Internal power system transformer testing and maintenance
Advantages
Compliance with Latest International Standards
Fully meets IEC 60044 international standard and Chinese national standards → test results are recognized by power systems worldwide
Industry-Leading Variable Frequency Technology
Reduces test voltage by 90% compared to traditional methods, eliminates the need for external auxiliary equipment → improves test safety and reduces equipment weight by 80%
0.05% Ultra-High Measurement Accuracy
The highest accuracy in its class, meets the test requirements of 0.1 accuracy class measuring transformers → ensures the reliability of power metering and protection systems
One-Click Full Automatic Test
Automatically completes all test items and generates standardized reports → reduces test time by 70% and eliminates human errors
Comprehensive Test Functions
Covers all CT and PT test items required by standards → one instrument replaces multiple traditional test equipment
FAQ
Q: What is the advantage of variable frequency test technology compared to traditional power frequency methods?
A:
- Safety: Reduces test voltage by 90% (e.g., testing a 45kV knee voltage CT only requires 450V at 5Hz), greatly improving test safety
- Portability: Eliminates the need for large and heavy external current boosters and voltage boosters, reducing equipment weight from over 100kg to only 12kg
- Efficiency: Completes all test items in one connection, no need to change wiring for different tests
- Accuracy: Avoids the influence of power grid interference on test results, ensuring higher measurement accuracy
Q: Can it test transient CTs (TPY, TPZ)?
A: Yes. CPT-31 supports testing all types of transient CTs including TPS, TPX, TPY and TPZ. It can measure their transient parameters such as time constant, saturation coefficient and remanence coefficient, and generate transient response curves.
Q: Can it test capacitive voltage transformers (CVT)?
A: Yes. CPT-31 supports testing all types of inductive PTs and capacitive PTs (CVT). It can measure their ratio error, phase angle error, secondary resistance and secondary burden, and verify their accuracy class.
Q: How long does a typical CT test take?
A: A complete CT test including ratio, polarity, volt-ampere characteristic, error curve, secondary resistance and secondary burden takes approximately 5~10 minutes using the one-click automatic test function. This is much faster than traditional methods which usually take 30~60 minutes.
Q: Does it require external power supply for on-site testing?
A: No. CPT-31 has a built-in high-capacity lithium-ion battery that provides more than 4 hours of continuous operation, which is sufficient for a full day of on-site testing. It also supports AC 220V power supply for long-time testing.
