Medium-Voltage Epoxy-Cast PTs | Elevate Power Distribution: Explore Premium Voltage Transformers | CIC

Coil Molded Single-Phase Voltage Transformers, or Potential Transformers, for Indoor Use (EP-3SF/6SF Series) / 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.

Featured Products

Coil Molded Single-Phase Voltage Transformers (Potential Transformers), 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 Coil Molded Single-Phase Voltage Transformers (Potential Transformers), 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.


Coil Molded Single-Phase Voltage Transformers (Potential Transformers), Indoor Use

EP-3SF/6SF Series

Voltage transformers of the EP-3SF/6SF Series are coil-molded, single-phase, indoor-type, medium-voltage, epoxy-resin-insulated potential transformers suitable for power systems of 7.2kV or below. Made with either a laminated core (Model EP-3SF2) or a cut core (EP-3SF5 & EP-6SFK), the voltage transformer has two power fuses attached to the primary side. Specific models from this series can be used as an auxiliary power source for circuit breaker operation — that is, as a control power transformer (CPT), also referred to as a control transformer (CTR), industrial control transformer, or machine tool transformer.

Medium-Voltage Epoxy-Cast PTs

About the Product

Intended for power systems of 7.2 kV or below, these single-phase coil molded voltage transformers, or potential transformers, are compact and economical. Model EP-3SF2 features a laminated core and is fixed by two metal frames; cut-core models EP-3SF5 and EP-6SFK are fitted on a metal base. All of the models come with two fuses on the primary side and are insulated with Araldite® epoxy resin. The EP-3SF/6SF Series is characterized by high moisture resistance and excellent electrical properties. In addition, the EP-6SFK model can be used as an auxiliary power source for circuit breaker operation (see Specifications).


(Model: EP-3SF2) Coil Molded Potential Transformer, Cut-Core

EP-3SF2

(Model: EP-3SF5) Coil Molded Potential Transformer (Cut Core)

EP-3SF5

(Model: EP-6SFK) Coil Molded Potential Transformer (Cut Core)

EP-6SFK

Specifications*

EP-3SF/6SF Series Coil Molded Single-Phase Potential Transformers - Specifications

* Other standards and specifications available.
** Models with a burden rating of 1000 VA or higher can be used as an auxiliary power source, also called a control transformer (CTR) or control power transformer (CPT), for circuit breaker operation (accuracy N/A).


Download Documents

Related Products
  • Voltage Transformers (Potential Transformers) as Circuit Breaker Operation Power Source
    Voltage Transformers (Potential Transformers) as Circuit Breaker Operation Power Source
    EPF-3SF1, EPF-6SF2

    Voltage transformers EPF-3SF1 and EPF-6SF2 are medium-voltage, indoor-type potential transformers cast in epoxy resin, commonly installed on switchgear (3.3kV or 6.6kV) to serve as an auxiliary power source* for circuit breaker operation. Positioned atop the switch as an operational power source, these transformers can handle relatively high outputs for short durations. Featuring Class-F heat-resistant insulation material for the coils, each voltage transformer is equipped with two power fuses on the primary side to safeguard against overload and short-circuit currents.* Auxiliary power source: In this application, the voltage transformer may also be referred to as a "control power transformer" (CPT), "control transformer" (CTR), "industrial control transformer," or a "machine tool transformer."


  • Conductive Shield Voltage Transformer (Potential Transformer) for 24 kV 4-Way Switchgear (Also Operation Power Source)
    Conductive Shield Voltage Transformer (Potential Transformer) for 24 kV 4-Way Switchgear (Also Operation Power Source)
    EPF-20FB

    This voltage transformer is a single-phase, epoxy-resin-cast medium-voltage potential transformer designed to also function as an operation power source*, specifically paired with 24kV 4-Way Switchgear. It features a high-voltage elbow-type connector on the primary side and includes an internal high-voltage power fuse for protection. The exterior of the voltage transformer is coated with a conductive metal mixture for shielding, and waterproof treatment can be requested for the secondary side. The voltage transformer has a rated burden and accuracy of 600 VA / 3.0 CL.* Operation power source: In this application, the voltage transformer can also be referred to as a "control power transformer" (CPT), "control transformer" (CTR), "industrial control transformer," or a "machine tool transformer."


  • Indoor Low-Voltage Single-Phase Voltage Transformers (Potential Transformers)
    Indoor Low-Voltage Single-Phase Voltage Transformers (Potential Transformers)
    S-N Series

    Single-phase voltage transformers, or potential transformers, for indoor locations of lower humidity. Class-A insulation material. Used with measuring or monitoring instruments, or as an auxiliary power source in the main panel or motor control panel. In the latter usage, this product can be referred to as a "control power transformer" (CPT), "control transformer" (CTR), "industrial control transformer," or a "machine tool transformer."


  • 12 kV & 24 kV Epoxy-Cast Voltage Transformer (Potential Transformer) or Control Power Transformer, as Power Source for Circuit Breaker Operation and Lighting
    12 kV & 24 kV Epoxy-Cast Voltage Transformer (Potential Transformer) or Control Power Transformer, as Power Source for Circuit Breaker Operation and Lighting
    EPF-20DZ

    This voltage transformer, cast with self-extinguishing epoxy resin, is a medium-voltage, indoor-type, single-phase potential transformer for a 12kV or 24kV power system for measuring and monitoring voltage signals. With a continuous output capacity of 4000 VA (max.), it can also serve in a small substation or a switchgear panel as a power source for circuit breaker operation and lighting equipment*.* Power source for circuit breaker operation and lighting equipment: In this application, the voltage transformer can also be referred to as a "control power transformer" (CPT), "control transformer" (CTR), "industrial control transformer," or a "machine tool transformer."


  • 3.6 kV Current Transformer, Coil Molded
    3.6 kV Current Transformer, Coil Molded
    EW-3S

    For measuring or monitoring instruments, this medium-voltage, indoor, coil molded current transformer is often used with the main panel or the motor control panel of a 3.6 kV (max.) power system. Insulated with Araldite® epoxy resin. Compact and easy to install.


  • Two-Core Coil Molded Current Transformer with Cut Cores, 3.6 kV
    Two-Core Coil Molded Current Transformer with Cut Cores, 3.6 kV
    EW-3C

    2-core (core type: cut-core), medium-voltage coil molded current transformer. Often used with the main panel or the motor control panel of a 3.6 kV (max.) power system. Good for protection. Suited to measuring and monitoring instruments. Araldite® epoxy resin.


  • 3.6 kV / 7.2 kV Current Transformers (1-Core / 2-Core & Single-Ratio / Dual-Ratio Options)
    3.6 kV / 7.2 kV Current Transformers (1-Core / 2-Core & Single-Ratio / Dual-Ratio Options)
    CR-3(6)S-T Series

    Intended for the main panel or the motor control panel of a 3.6/7.2 kV power system and designed to be used with measuring or monitoring instruments, or with protective relays. Each CT has a busbar terminal. Insulated with Araldite® epoxy resin.


  • 3.6 kV Two-Core Epoxy-Cast Current Transformer
    3.6 kV Two-Core Epoxy-Cast Current Transformer
    ER-3C

    Offering a higher rated current ratio, this medium-voltage, two-core current transformer is suited to the main panel or the motor control panel of a 3.6 kV (max.) power system and can be used with measuring or monitoring instruments, or with protective relays. Araldite® epoxy resin.


  • Epoxy-Cast Window-Type Current Transformers for Indoor Application, 3.6 kV
    Epoxy-Cast Window-Type Current Transformers for Indoor Application, 3.6 kV
    CR-3S Series

    2-core & single-core models. Indoor window-type current transformers for the main panel or motor control panel of a MV (≦ 3.6 kV) power system. Good for protection and appropriate for measuring and monitoring instruments. Araldite® epoxy resin.