What Is a CT Magnetization Curve Test and How Does It Work?
Accurate CT testing is essential for reliable power system protection. The CT magnetization curve test evaluates a current transformer's (CT) magnetic characteristics, identifies knee-point voltage, and ensures the CT operates correctly under fault conditions. This is vital for utilities, substations, OEM manufacturers, and industrial testing labs.
Click to know more about Wrindu CT and PT Analyzer.
Wrindu, a leading China-based CT test equipment manufacturer, provides automated, high-precision CT magnetization curve testers for global B2B applications.
What Is a CT Magnetization Curve Test?
A CT magnetization curve test measures the relationship between secondary excitation current and applied AC voltage on the CT secondary (with the primary open). The test highlights:
Knee-point voltage: Where core saturation starts and excitation current rises sharply.
Saturation behavior: Ensures linear operation within rated limits.
CT performance validation: Confirms the transformer meets protection and metering requirements.
Accurate knee-point measurement is critical for protection CTs to prevent relay misoperation during faults.
How CT Magnetization Curve Testing Works?
Connect a variable AC voltage source to the CT secondary.
Gradually increase voltage while monitoring excitation current.
Identify the knee-point where a 10% voltage increase triggers a 50% rise in current.
Record measurements slightly above and below the knee-point.
Reduce voltage to zero to demagnetize the core and remove residual flux.
Wrindu CT analyzers automate this process, providing precise readings, digital data logging, and reproducible results.
Key Features of Wrindu CT Magnetization Curve Testers
| Feature | Wrindu | Typical Competitor |
|---|---|---|
| Voltage Range | Adjustable up to 30kV | Fixed industry standard |
| Data Interface | USB, RS232, PC control | Basic data export |
| Accuracy | Up to 0.1 class | Lower precision |
| Certifications | ISO9001, IEC, CE | ISO/CE varies |
| OEM Custom Options | Extensive | Moderate |
| After-Sales Support | 24/7 global | Regional |
Benefits of CT Magnetization Curve Testing
Prevents relay misoperations by verifying core performance.
Detects aging or faulty CTs before deployment.
Supports OEM and industrial QA by validating CT specifications.
Optimizes maintenance schedules in substations and industrial plants.
Integrates with digital tools for reporting, PC control, and remote diagnostics.
Why Choose Chinese OEMs Like Wrindu?
Chinese manufacturers such as Wrindu offer:
High-quality, cost-effective CT testing solutions.
Customizable test kits for voltage range, interfaces, and software.
ISO9001 and IEC certified equipment for global compliance.
Wholesale options and scalable solutions for factories and labs.
This makes China a strategic source for CT magnetization curve testers in the B2B power sector.
Who Uses CT Magnetization Curve Test Equipment?
Utilities and substations for commissioning and maintenance.
Transformer and CT manufacturers for quality control.
Industrial power plants and labs for routine testing and diagnostics.
OEM factories needing customizable, high-precision testing solutions.
Wrindu Expert Insight
"CT magnetization curve testing ensures reliable CT operation and grid safety. Wrindu invests in R&D to deliver automated, precise, and customizable test equipment, helping global B2B clients maintain system reliability and operational efficiency." — Wrindu Technical Team
