Indoor and Outdoor Current Transformers | Elevate Power Distribution: Explore Premium Voltage Transformers | CIC

Low-Voltage, Medium-Voltage & High-Voltage Current Transformers | Serving a diverse client base around the world, CIC is a leading manufacturer and supplier of current transformers, potential transformers (voltage transformers), distribution transformers, epoxy insulators, electronic meters, and other electrical and electronic products.

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Current Transformers (CT) - Instrument Transformers | Revolutionize Your Energy Systems with Advanced Distribution Transformers | CIC

Based in Taiwan since 1974, CHALLENGE INDUSTRIAL CO., LTD. specializes in manufacturing high-quality electrical products, including Current Transformers (CT) - Instrument Transformers, current transformers, voltage transformers, distribution transformers, epoxy insulators, and power capacitors. With over 45 years of expertise and technology collaboration with Germany's MWB, CIC is ISO certified and offers products recognized for reliability in various industrial applications.

Challenge Industrial Co., Ltd. (CIC) stands at the forefront of electrical innovation, specializing in the manufacturing of current transformers, voltage transformers, distribution transformers, epoxy insulators, and power capacitors. With a legacy built on over 45 years of engineering excellence and leveraging advanced German technology, CIC commits to delivering high-quality, ISO-certified electrical solutions. Their comprehensive product range, paired with an ISO-certified approach and a TAF-accredited laboratory, ensures reliability and performance for a diverse global market. CIC is your go-to source for electrical components that power progress and efficiency.

CIC has been offering customers high-capacity power capacitors since 1974, both with advanced technology and 45 years of experiences, CIC ensures each customer's demands are met.

Current Transformers (CT) - Instrument Transformers

Low-Voltage, Medium-Voltage & High-Voltage Current Transformers

Indoor and Outdoor Current Transformers
Indoor and Outdoor Current Transformers

Current transformers, abbreviated as CT, are specialized transformers used in AC electrical circuits. Together with voltage transformers (VT), they are collectively known as "instrument transformers." Current transformers function by transforming higher current (I1) on their primary side into lower current (I2) on their secondary side, maintaining a specific ratio. Typically, the secondary current is transformed into 5A or 1A, as prescribed by current IEC and IEEE regulations. The transformed current can be easily and safely measured, serving the purpose of monitoring and measuring electricity consumption in circuits and systems. Current transformers can also play a crucial role in providing protection to the primary side electrical circuits.

Current transformers can be classified into low-voltage current transformers, typically used in electrical circuits below 600V, and medium-voltage (MV) and high-voltage (HV) current transformers, which cater to power lines with voltages exceeding 600V. Depending on their application, current transformers can be divided into indoor and outdoor variants, as well as those used for measurement or protection purposes.

CIC: Leading the Way in Advanced Current Transformers

CIC combines decades of research, development, and manufacturing experience with advanced technology transferred from Germany's MWB Messwandler-Bau. CIC designs and produces a wide range of high-quality, versatile current transformers, making it the first manufacturer in Taiwan to use epoxy resin as the primary insulation material for current transformers. CIC's indoor current transformers primarily use Araldite® epoxy resin as the insulating material, while the outdoor models use UV-resistant cycloaliphatic epoxy resin.

Current transformers by CIC undergo type tests and routine tests performed by CIC's Advanced Electricity Lab, accredited by TAF (ILAC member). This comprehensive approach ensures consistent operations from the design and prototype stages to mass production and factory testing, allowing for precise control of product quality and delivery times.

CIC offers a diverse range of current transformer types to meet various customer needs, including accuracy, insulation levels, materials, design, and physical dimensions. The company also provides customized solutions tailored to specific requirements, usage scenarios, and locations. CIC offers ODM/OEM services and manufactures products complying with various international regulations. CIC’s current transformers have successfully reached markets in countries such as the United States, Canada, Russia, and Japan, and have found extensive applications in power companies, factories, major projects, and construction firms, particularly for billing, power supply, and distribution projects.


Click on any category below to explore our products. You can also contact us directly and the CIC team will be happy to assist you.



  • Low-Voltage (LV) Current Transformers (CT) 0.72 kV max.
    Low-Voltage (LV) Current Transformers (CT) 0.72 kV max.
    Low-Voltage CT Instrument Transformers

    Low-voltage current transformers by CIC are manufactured in two main insulation styles: ABS-encased or cast-resin types. In terms of structure, the LV current transformer series offers different variations, including window-type and split-core models. Functionally, there are two main types: metering (measurement) CTs and protection CTs. There are also zero-phase current transformers (ZCTs) suitable for outdoor or indoor use by utility companies or high-voltage end-users to protect against high-voltage power cable leakage and support other monitoring needs. This product line also includes special types, such as dry-type bushing current transformers (BCT), ideal for GIS switches or transformer bushings.All types and specifications of current transformers from CIC undergo type tests and routine tests conducted by CIC's Advanced Electricity Lab, accredited by the ILAC member TAF, ensuring product quality.With over 45 years of professional experience, CIC manufactures a wide range of high-quality and versatile current transformers. Our diverse product specifications cater to the needs of various customer groups. We also offer customization and ODM/OEM services. Due to the high precision and stable quality of our products, they are widely adopted in billing, power supply, and distribution projects by utility companies, factories, major engineering ventures, and construction companies worldwide.


  • Medium-Voltage (MV) Current Transformers (CT) 3.6-7.2 kV
    Medium-Voltage (MV) Current Transformers (CT) 3.6-7.2 kV
    Epoxy Resin Cast CT Instrument Transformers for Control Panels

    Current Transformers 3.6-7.2 kV Series are primarily used for measurement, monitoring, or protection in motor control panels and other equipment. Models include single/double core epoxy resin CTs, coil molded CTs, terminal type, window type, and more. The main insulation material is Huntsman (formerly Ciba-Geigy of Switzerland) Araldite® epoxy resin. Current transformers can be manufactured according to IEC, IEEE, or other standards. Outdoor current transformers are also available per customer requirements.Type tests and routine tests for CIC’s medium-voltage current transformers are all conducted by CIC's Advanced Electricity Lab, accredited by ILAC member TAF, ensuring quality. With decades of experience, CIC manufactures current transformers in a wide variety of specifications to meet diverse customer needs, also offering customization and ODM/OEM services. Thanks to high accuracy and reliable quality, CIC's products are widely used for metering and distribution by utilities, factories, major projects and builders globally.


  • Medium-Voltage (MV) Current Transformers (CT) 12-24 kV
    Medium-Voltage (MV) Current Transformers (CT) 12-24 kV
    Indoor & Outdoor Epoxy Resin Cast CT Instrument Transformers

    Current Transformers 12-24 kV Series include CIC’s long-selling, well-received 24 kV epoxy-resin-cast CTs “EWF-20 series” with over 20 years of proven quality and practical design. Other major product lines include outdoor metering ERCTs, multi-ratio bushing CTs (for withdrawable switchgear), indoor CTs for regions with polluted air, CTs for SF6-insulated MOF switchgear, and dual-core cast-resin CTs with U-groove design on top.CIC primarily uses Huntsman Araldite® epoxy resin insulation for indoor CTs, while outdoor current transformers feature special cycloaliphatic epoxy resin for UV resistance. All type tests and routine tests for CIC's Medium-Voltage Current Transformers are conducted in CIC’s Advanced Electricity Lab, accredited by the ILAC member TAF, ensuring the highest quality standards. With decades of experience in manufacturing current transformers, CIC offers a wide range of specifications to meet the diverse needs of a broad customer base. We also provide customization and ODM/OEM services. Thanks to the high precision and reliable quality of our products, they are widely adopted in billing and distribution projects by utility companies, factories, major engineering ventures, and construction companies around the world.


  • Medium-Voltage (MV) Current Transformers (CT) 36 kV
    Medium-Voltage (MV) Current Transformers (CT) 36 kV
    Indoor, Outdoor & Multi-Ratio CT Instrument Transformers & ERCT for Metering Units

    Current Transformers 36 kV Series encompass both indoor and outdoor CTs, including multi-ratio CTs with two or more iron cores and MV revenue-metering current transformers suitable for 36 kV systems, such as ERCT (Extended Range Current Transformers) for MOF metering units. CIC's epoxy resin cast current transformers use internationally renowned Huntsman's Araldite® epoxy resin, while outdoor models utilize UV-resistant cycloaliphatic epoxy resin to maintain stable quality.All type tests and routine tests for CIC's 36 kV Medium-Voltage Current Transformers are conducted in CIC’s Advanced Electricity Lab, accredited by the ILAC member TAF. With decades of experience, CIC manufactures current transformers in diverse specifications to meet various customer needs, also providing customization and ODM/OEM services. Thanks to high accuracy and reliable quality, CIC's products are widely used for metering and distribution by utilities, factories, major projects and builders globally.


  • High-Voltage (HV) Current Transformers (CT) 46-72.5 kV etc.
    High-Voltage (HV) Current Transformers (CT) 46-72.5 kV etc.
    Outdoor CT Instrument Transformers for Metering & Other Applications

    High-Voltage Current Transformers by CIC are manufactured using Araldite® UV-resistant cycloaliphatic epoxy resin, renowned for its exceptional electrical and mechanical properties. This series of outdoor or indoor current transformers is available in versatile designs and can be offered with multiple iron cores and various specifications, catering primarily to substations or high power loads. They are commonly used for electricity billing, system monitoring, and protection.CIC's outdoor high-voltage current transformers are recognized for their excellent design and construction, making them ideal for humid, high-salt, or highly polluted areas, such as island regions or offshore wind power installations. Furthermore, their user-friendly design ensures easy installation and maintenance.CIC, with the transfer of advanced technology from MWB Messwandler-Bau in Germany, has strengthened its decades-long research, design, and manufacturing capabilities. As the first Taiwanese manufacturer to use epoxy resin as the primary insulation material for instrument transformers, CIC produces a wide range of high-quality and versatile current transformers and voltage transformers. CIC excels in providing custom CTs, VTs (PTs), and ODM/OEM services and are trusted by utility companies, factories, major projects, and construction firms worldwide for metering and distribution projects.