Current Transformer (CT)
Your Leading Current Transformer (CT) Supplier
Trust In Grid Co., Ltd. is a professional transformer manufacturer, specializing in the design and production of power transformer, high-voltage switchgear, power distribution equipment, energy storage systems (ESS), magnetic wire, bushing and machining parts. Our power transformers are available in 500KV, 330KV, 220KV, and 110KV models, and are widely used in power utilities, renewable energy systems (solar and wind), industrial facilities, data centers, transportation infrastructure, and OEM applications.
Why Choose Us?
Production Capacity
With 6 factories covering 240,000 m², over 2,000 employees, and 200+ engineers, we support large-scale projects and long-term global supply with more than 30 years of export experience.
Advanced Equipment
We operate a complete set of in-house production equipment, including cutting, winding, CNC machining, vacuum drying, and testing systems, with over 450 machines ensuring stable quality and efficient output.
Quality Control
All products are manufactured and tested in compliance with IEC, IEEE, ANSI, CSA, UL/cUL, CE, and ISO 9001:2015 standards, ensuring reliable performance and smooth international approval.
OEM & ODM Capability
Our engineering team provides OEM/ODM support, including customized design and technical optimization, delivering tailored solutions for utility, industrial, and renewable energy projects.
Technical Specifications of Current Transformer (CT)
|
Item |
Parameter |
|
Rated Voltage |
220kV |
|
Rated Primary Current |
Typically covers the range from 200A to 2500A |
|
Rated Secondary Current |
1A or 5A |
|
Rated Short-Time Thermal Current |
E.g., 31.5kA (3s) |
|
Rated Dynamic Current |
E.g., 120kA |
|
Partial Discharge Level |
≤ 10 pC (at specified test voltage) |
|
Dielectric Dissipation Factor (tanδ) |
≤ 0.005 |
|
Insulation Level |
Rated lightning impulse withstand voltage up to 950kV, rated power frequency withstand voltage up to 395kV |
- Provides galvanic isolation between high-voltage and low-voltage circuits, ensuring safety for operators and equipment.
- High accuracy in current measurement, allowing precise monitoring and control of electrical currents.
- Wide dynamic range, capable of measuring both high and low currents with high accuracy.
- Low insertion impedance, minimizing the impact on the primary circuit and maintaining system efficiency.
- Ability to handle high fault currents and transient conditions without damage.
- Provides a proportionate reduced current output that can be easily interfaced with measuring instruments and relays.
- Enables multiple measurements to be taken from a single primary conductor, reducing the need for additional current-carrying conductors.
- Enhances system reliability by enabling early detection and protection against overcurrents and faults.
- Can be easily integrated into existing power systems without major modifications.
- Suitable for both AC and DC applications, depending on the specific design and configuration.
Energy metering
CTs are the basis of power metering, enabling utilities and consumers to accurately measure energy consumption. By reducing high currents in the distribution system to a measurable level, CTs can achieve precise billing and energy monitoring.
Protection systems
In protection relays and circuit breaker control, CTs provide key information about the current flowing through circuits. These data help detect abnormal situations such as overload or short circuits and initiate protection measures to isolate and protect equipment.
Control and monitoring
Industrial automation and control systems use CTs to monitor the current levels of motors, transformers, and other equipment. This monitoring helps manage system performance and efficiency while ensuring components operate within safe parameters.
Renewable energy systems
In renewable energy installations such as wind farms and solar power plants, CTs are used to monitor the current from the generator to the grid. They ensure the efficient and safe operation of the system and provide data for performance optimization.
Safety and instrumentation
CTs help ensure personnel safety through the use of isolated measuring instruments. By providing a low-level secondary current, CT enables the safe operation of instruments and sensors. Otherwise, if directly connected to a high-current circuit, there would be a risk.
How to Choose Current Transformer (CT)
Application
If you need accurate billing and measurement → Choose Metering CT.
If your priority is system protection → Choose Protection CT.
Current Ratio
Match the CT ratio to the primary circuit current.
Accuracy Class
Metering CTs → Accuracy classes like 1.0, 0.2, 0.5.
Protection CTs → Classes like 5P5, 5P10, 10P10.
Burden (VA Rating)
The load connected to CT secondary (meters, relays, wires). Ensure the CT can handle it.
Standards Compliance
Look for CTs that comply with IEC 61869, IS 2705 or relevant BIS standards.
Saturation & Safety
Protection CTs must avoid saturation during faults.
Metering CTs must not saturate under normal operation.
Customization Options
Understand how Current Transformers and Potential Transformers differ in function, construction, and usage for safe and accurate power system measurement.
Material: Customizable
Logo: Customizable
Structure: Customizable
MOQ: Customizable
The Difference Between Current Transformer (CT) and Voltage Transformer (VT or PT)
Understand how Current Transformers and Potential Transformers differ in function, construction, and usage for safe and accurate power system measurement.
|
Feature |
Current Transformer (CT) |
Potential Transformer (PT) |
|
Basic Function |
Converts high current to low current for safe measurement. |
Converts high voltage to low voltage for safe measurement. |
|
Connection Method |
Connected in series with the power line. |
Connected in parallel with the power line. |
|
Primary Winding Role |
Carries the actual line current being measured. |
Maintains and measures the line voltage. |
|
Primary Winding Turns |
Very few turns on the primary side. |
Many turns on the primary side. |
|
Secondary Winding |
Has many turns. Must never be open-circuited during operation. |
Has fewer turns. Can be open-circuited without damage. |
|
Secondary Output |
Standard output: 5A or 1A. |
Standard output: 110V. |
|
Transformation Ratio |
High transformation ratio (because the primary current is high). |
Low transformation ratio (because the primary voltage is high). |
|
Main Use |
Used to measure very high current safely. |
Used to measure very high voltage safely. |
* Although CTs and PTs look similar on the outside, their internal structures are quite different.
Ordering Process
Send Us Inquiry → Receive Our Quotation → Negotiate Details → Confirm the Sample → Sign Contract/Deposit → Mass Production →cargo Ready → Balance/Delivery → Further Cooperation
Payment Terms
T.T with 30% downpayment, 70%before shipment.
Paypal or West Union also accept.
Our Service Highlights
Pre-Sales Consultation & Design Support
Early technical engagement to define requirements and deliver optimized solutions.
During Sales & Project Execution
Transparent project management with controlled production, quality tracking, and on-time delivery.
Warranty Advantage
Minimum 2-year warranty on all products, ensuring reliable and risk-free operation.
After-Sales Support
24/7 technical support with fast response, spare parts availability, and training services.
Long-Term Partnership
Lifelong technical support and upgrade guidance for sustained performance.
Packaging & Shipping
Packaging details:
Shockproof foam/moisture-proof film, professional export cartons/wooden crates/pallets.
Final assembly ensures mechanical integrity and readiness for transportation and installation.
Certificates
We're well-known as one of the leading current transformer (ct) manufacturers and suppliers in China, also support customized service. Please feel free to buy high quality current transformer (ct) made in China here from our factory. Contact us for more details.
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