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
YK transformer distributor .jpg

YK Series Current Transformer - Reliable AC Measurement Solutions from China Suppliers and Factory

,

A current transformer (CT) is a crucial electrical device used for controlling, monitoring, and protecting power systems. This essential equipment converts large alternating currents (AC) into smaller, measurable quantities, making it indispensable in various applications such as power generation, transmission, and industrial settings. By enabling the connection of high-current power circuits to sensitive measuring devices or protective relays, current transformers play a vital role in ensuring efficient and safe operations. As a leading manufacturer and supplier in China, our factory specializes in delivering high-quality current transformers designed to meet the diverse needs of our clients.

,
    Contact us
    Product Details

    Product Overview

    A CT is powered by electromagnetic induction and consists of two windings: a main winding (few turns connected in series with the high-current circuit) and a secondary winding (many turns connected to safety or measurement devices). While the primary winding receives a large current, the secondary winding — which is typically specified at 5A or 1A for the majority of industrial applications — receives a low current.

    ⚡
    This proportionality, sometimes referred to as the transformation ratio, protects personnel and equipment from potentially dangerous voltages while enabling precise current measurement.

    CTs need strong insulation to sustain high voltage between windings, good linearity to reduce measurement error, and high precision for energy metering.

    ⚠️
    When employing a CT, the secondary winding should never be open-circuited. An open circuit can produce extremely high voltages that could damage electrical equipment.

    In summary, because they provide more precise current monitoring and improved fault protection, current transformers are essential for guaranteeing the dependability, effectiveness, and safety of contemporary electrical systems.

    Technical Parameters

    Type Main Loop Current (mm) Outline Size
    YK-30 < 63 30 89 70 28 80
    YK-45 < 100 45 104 85 28 95
    YK-65 < 250A 65 124 105 28 115
    YK-80 — 80 142 122 28 132
    YK-100 < 630A
    Current: 1A    		 100 162 142 28 152
    Rated Primary — Rated Second Current: 0.5mA

    * Outline size columns represent dimensional parameters in millimeters for each CT model.

    Frequently Asked Questions

    Q
    What is a Current Transformer (CT) and how does it work?
    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 measuring or protection devices. The CT steps down a large primary current to a smaller, proportional secondary current — typically 5A or 1A — safe for instrumentation use.
    Q
    Why should the secondary winding of a CT never be left open-circuited?
    If the secondary winding is left open while the primary carries current, the magnetic flux in the core becomes unsaturated and generates an extremely high voltage across the open terminals. This can damage the CT insulation, connected equipment, and poses a serious safety hazard to personnel. Always ensure the secondary is connected to a burden or short-circuited when not in use.
    Q
    What is the transformation ratio in a CT?
    The transformation ratio refers to the proportional relationship between the primary (high) current and the secondary (low) current output of the CT. For example, a CT with a ratio of 100:5 means that for every 100A flowing in the primary, 5A flows in the secondary. This ratio enables accurate current measurement without direct contact with high-voltage circuits.
    Q
    What are the key performance requirements for a current transformer?
    A high-quality CT must meet three critical performance criteria: (1) Strong insulation — to withstand high voltages between primary and secondary windings; (2) Good linearity — to minimize measurement errors across the operating range; and (3) High precision — essential for accurate energy metering and billing applications.
    Q
    Which YK series CT model is suitable for currents up to 630A?
    The YK-100 model is designed to handle main loop currents up to 630A with a rated secondary current output of 1A. It features an outline size of 100mm with overall dimensions of 162 × 142 × 28 × 152mm, making it suitable for high-current industrial measurement and protection applications.
    Q
    What is the rated secondary current output for the YK series current transformers?
    According to the technical parameters, the YK series current transformers have a rated secondary current of 0.5mA. The YK-100 model additionally specifies a rated current of 1A for its primary configuration, making it versatile for various metering and protection relay applications in industrial environments.