Medium-Voltage Potential Transformers | Elevate Power Distribution: Explore Premium Voltage Transformers | CIC

12/24 kV Epoxy-Cast Voltage Transformers, or Potential Transformers, for Indoor Use. (Models: EPF-10B/20SE/20SI) / 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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12 kV & 24 kV Epoxy-Cast Voltage Transformers (Potential Transformers) for Indoor Use | Enhance Safety and Performance with Superior Epoxy Insulators | CIC

Based in Taiwan since 1974, CHALLENGE INDUSTRIAL CO., LTD. specializes in manufacturing high-quality electrical products, including 12 kV & 24 kV Epoxy-Cast Voltage Transformers (Potential Transformers) for Indoor Use, 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 50 years of experiences, CIC ensures each customer's demands are met.


12 kV & 24 kV Epoxy-Cast Voltage Transformers (Potential Transformers) for Indoor Use

EPF-10B/20SE/20SI

Widely used for 12~24 kV power systems and insulated with Araldite® epoxy resin, these voltage transformers, or potential transformers, are characterized by superior moisture resistance and excellent electrical properties. Customizable for different standards and requirements.

Medium-Voltage Potential Transformers

About the Product

EPF-10B, EPF-20SE, and EPF-20SI voltage transformers, or potential transformers, have been widely used for 12~24 kV power systems. Insulated with Araldite® epoxy resin and characterized by superior moisture resistance and excellent electrical properties, these voltage transformers have met with a high level of customer satisfaction in numerous countries.   

EPF-10B, EPF-20SE, and EPF-20SI voltage transformers, or potential transformers, are known for their durability. In particular, Model EPF-20SE has, as requested by customers, undergone stringent environmental testing (Thermal Cycling Testing), in which the voltage transformer withstood 20 temperature cycles (from -40 to +65℃), lasting approximately 240 hours.

All three models can be customized to meet the requirements of different standards and specifications.

Product Features

  • Cast in Araldite® epoxy resin
  • Indoor usage
  • Standard: IEC or IEEE*
  • System Voltage: 12~24 kV
  • Frequency: 50 or 60 Hz
(Model: EPF-10B) Epoxy-Cast Potential Transformer(Model: EPF-20SE) Epoxy-Cast Potential Transformer(Model: EPF-20SI) Epoxy-Cast Potential Transformer
EPF-10BEPF-20SEEPF-20SI

Selection Table

10/20kV Epoxy-Cast Potential Transformers Specifications (Models: EPF-10B/20SE/20SI)

*Other standards and specifications available.

Available Models

EPF-10B, EPF-20SE, EPF-20SI


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