Inquiry Now
Leave Your Message
Products Categories
Featured Products
SFM118 Series Single Phase Multifunction Meter

SFM118 Series Single Phase Multifunct...
SFM472 Series Three Phase Multifunction Meter

SFM472 Series Three Phase Multifuncti...
Three Phase Digital Combined Meter

Three Phase Digital Combined Meter
Multifunctional watch LED

Multifunctional watch LED
Three Phase Digital Voltmeter, Ammeter

Three Phase Digital Voltmeter, Ammeter
SFN-9K6-3UI Digital Combined Meter

SFN-9K6-3UI Digital Combined Meter
Single Phase Multifunctional Power Instrument

Single Phase Multifunctional Power In...
Single Phase Digital Combined Meter

Single Phase Digital Combined Meter
Power factor meter

Power factor meter
Single-phase meter

Single-phase meter
0102030405
CT3D transformer supplier .jpg

China CT3D Series Current Transformer - Top Suppliers & Factory for Power Management Solutions

,

Discover the essential role of a current transformer (CT) in the electrical industry, particularly for power management, monitoring, and safeguarding your energy supply. As a leading supplier in China, we manufacture high-quality CTs that effectively transform large alternating currents (AC) into smaller, measurable units. Our products are ideal for power generation, transmission, distribution, and industrial applications, ensuring safe connections with relays and sensitive measurement devices. Trust our factory for reliable solutions that enhance your electrical systems.

,
    Contact us
    Product Details

    Product Overview

    A CT operates on electromagnetic induction and has two windings: a main winding with a few turns linked in series to the high-current circuit, and a secondary winding with many turns connected to safety or measurement devices. The primary winding receives a significant current, but the secondary winding — which is usually tuned to 5A or 1A for most industrial applications — receives very little current. This proportionality, also known as the transformation ratio, allows for accurate current monitoring while safeguarding workers and equipment from potentially dangerous voltages.

    • ⚡ Linearity: Required to minimize measurement error and ensure reliable readings.
    • 🎯 High Precision: Essential for accurate energy metering in industrial applications.
    • 🛡️ Insulation: Sufficient insulation must be maintained between windings at all times.
    • 🔌 Transformation Ratio: Enables precise current monitoring across a wide range.
    ⚠️

    Important Safety Notice: When utilizing a CT, you should never leave the secondary winding open circuit. This is owing to the likelihood of extremely high voltages generated by an open circuit, which might seriously harm electrical equipment and personnel.

    Current transformers are critical to ensuring the reliability, efficacy, and safety of modern electrical systems because they enable more precise current monitoring and improved issue diagnosis.

    Technical Parameters

    Type Specification (mm) Outline Size
    A B C D E F G
    CT3D-100 100A/5A 122.5 78.5 43 35.5 22 19.5 76
    CT3D-250 250A/5A 134 84.5 43 35.5 27 22 87
    CT3D-400 630A/5A 173.5 109 43 35.5 37 32 127
    CT3D-630 1000A/5A 211 120 43 35.5 44 46 165
    Accuracy Grade: 1.0 Overload Current: ≥1.2% In

    Frequently Asked Questions

    Q What is a Current Transformer (CT) and how does it work?
    A A Current Transformer (CT) operates on the principle of electromagnetic induction. It consists of a primary winding connected in series with the high-current circuit and a secondary winding connected to measurement or protection devices. The CT steps down the high primary current to a safer, proportional secondary current — typically 5A or 1A — suitable for metering and protection equipment.
    Q Why should the secondary winding of a CT never be left open circuit?
    A If the secondary winding of a CT is left open circuit while current flows through the primary, the transformer will generate an extremely high voltage across the open terminals. This can cause severe damage to the transformer insulation, connected equipment, and poses a serious safety risk to personnel. Always ensure the secondary circuit is closed or properly short-circuited when the CT is energized.
    Q What accuracy grade do the CT3D series current transformers offer?
    A The CT3D series current transformers offer an accuracy grade of 1.0, making them suitable for energy metering and industrial measurement applications where reliable and precise current readings are required. They also support an overload current of ≥1.2% In.
    Q What current ratios are available in the CT3D series?
    A The CT3D series is available in multiple current ratios to suit different application requirements: CT3D-100 (100A/5A), CT3D-250 (250A/5A), CT3D-400 (630A/5A), and CT3D-630 (1000A/5A). All models output a standardized 5A secondary current for easy integration with standard metering and protection devices.
    Q What are the key performance requirements for a current transformer?
    A A high-quality current transformer must meet three key performance requirements: Linearity — to minimize measurement error across the full operating range; High Precision — to ensure accurate energy metering results; and Adequate Insulation — to maintain safe voltage isolation between the primary and secondary windings and protect both equipment and personnel.
    Q What is the transformation ratio and why is it important?
    A The transformation ratio is the proportional relationship between the primary current and the secondary current of a CT. It allows high currents that would be unsafe or impractical to measure directly to be accurately represented as a much smaller, manageable current on the secondary side. This ratio is critical for accurate current monitoring, energy metering, and protecting connected measurement and protection devices from dangerous voltages.