Current Transformer Manufacturer In-Depth Analysis: HEYI ELECTRICAL Overview and Product Guide

Current transformers (CTs) are essential components in power monitoring, energy metering, and grid management. As global electricity demand grows and renewable energy expands, choosing a reliable CT manufacturer becomes critical for procurement professionals, engineers, and system integrators. WENZHOU HEYI ELECTRICAL CO.,LTD., established in 2012, is a manufacturer specializing in bespoke current transformers and current sensors, offering a broad portfolio that serves smart grid, EV charging, solar, data center, and industrial applications.

Problem Definition: What to Look for in a Current Transformer Manufacturer

When evaluating current transformer manufacturers, buyers often face challenges around accuracy, installation flexibility, environmental durability, and customization. A manufacturer must demonstrate robust production capacity, compliance with international standards, and the ability to tailor products to specific project requirements. HEYI ELECTRICAL addresses these concerns with a product range covering split-core, solid-core, Rogowski coil, hall effect, leakage current, and revenue-grade CTs, all backed by a dedicated R&D team and a 10,000 m² facility.

Industry Background: Current Transformer Market Trends

The global current transformer market was estimated at USD 2.63 billion in 2024 and is projected to reach USD 3.90 billion by 2030 (Grand View Research). The Asia Pacific region accounted for 40.15% of the market in 2025 (Straits Research). Split-core current transformers are identified as the fastest-growing segment due to ease of installation in retrofit and smart grid applications (Fact.MR). EV charging infrastructure is another key growth driver, with the related component market expected to grow at a CAGR of 23.6% from 2025 to 2033.

Company Profile: HEYI ELECTRICAL

WENZHOU HEYI ELECTRICAL CO.,LTD. was founded in 2012. It operates a 10,000 m² manufacturing facility with an annual production capacity of 356,000 units. The company employs 56 staff, including a 5-engineer R&D team. Export business accounts for 95% of total sales, with major markets in Southeast Asia, South Korea, Europe, South America, Australia, Africa, the Middle East, and North America. The company’s products are trusted by global technology firms such as Siemens, Schneider Electric, LG, Samsung, and SoftBank.

Core Product Solutions

HEYI offers a comprehensive lineup of current transformers and sensors, each designed for specific applications:

Split-Core Current Transformer (KCT Series)

The KCT is a split-core current transformer with a clamp-on design, housing made of PA plastic, core of silicon steel sheets and ferrites, and winding of pure copper enameled wire. Inner diameter: 0–50 mm. Measurement range: 0–1000 A. Accuracy options: 3.0/1.0/0.5. Output options: 5 A, 1 A, mA, mV, RS485, 4-20 mA. Intended for solar/wind energy storage, smart grid, EV charging infrastructure, smart buildings, and data centers. Customizable lead wire type, length, and connector.

Three-Phase Current Transformer (DASN Series)

The DASN is a compact 3-phase measuring CT, DIN-rail mounted, 3-in-1 design. Measurement range 0–1000 A, accuracy class 1.0, secondary output 5 A, inner diameter 0–50 mm. Made of ABS/PC plastic, silicon steel sheets or nanocrystalline materials, and pure copper enameled wire. Intended for EPC solar/wind/storage, smart buildings, MCC, UPS, IDC & telecom, and main & branch monitoring.

Flexible Rogowski Coil (FRC Series)

The FRC is an air-core, non-saturating flexible Rogowski coil with integrator (G1). Inner diameter 245 mm, measurement range 100–10000 A, millivolt output. Made of silicone and pure copper enameled wire. Suitable for heavy industry, smelting, data center power retrofit, portable testing meters, and lightning/transient current measurement. Customizable inner diameter, output, and color.

Revenue-Grade Billing CT (RECT Series)

The RECT is an Extended Range Current Transformer (ERCT) compliant with IEEE C57.13, offering accuracy class 0.15S. Measurement range 0–1000 A, output 5 A/1 A, inner diameter 0–78 mm, IP65, UV protection. Made of epoxy resin, silicon steel sheets core, and pure copper enameled wire. Designed for utility & substation billing and utility-scale solar/wind plants. Customizable OEM.

Leakage Current Sensor (HYCA Series)

The HYCA is a 6mA DC leakage current sensor (RDC-PD) with differential current range 0–300 mA, resolution 0.2 mA. Frequency range DC–2 kHz, load current up to 80 Arms (1-phase) or 3×32 Arms (3-phase). Integrated self-monitoring and test functions, switching output for 6 mA DC and 30 mA AC per IEC 62752. Made of Nylon plastic and copper. Intended for EV charging infrastructure and solar/wind energy storage.

Other Key Series

• DX/DM: Compact low voltage CT (0.66 kV), DIN-rail mounted, accuracy 1.0/0.5, inner diameter 125×35 mm. Designed for high-vibration environments, EMU/high-speed rail, modular data centers.
• KCT-L: Loop-powered split-core current transmitter with 4-20 mA DC output, accuracy 1.0, inner diameter 0–50 mm. For IoT & Smart City, PLC/DCS integration, remote monitoring.
• DP/HK: Busbar split-core CT, measurement 0–8000 A, accuracy 3.0/1.0/0.5, large window 0–80×160 mm. For smart grid, solar/wind, data centers, EMS, IoT smart cities.
• OCT: Outdoor waterproof split-core CT, IP65, inner diameter 0–120 mm. For overhead line monitoring, railway trackside, municipal infrastructure.
• LMZW: Outdoor resin-cast CT, 0.66 kV, IP65. For RMU, chemical & metallurgy, marine & offshore.

Manufacturing Capability and Quality Control

HEYI operates a 10,000 m² factory with an annual output of 356,000 units. The 5-engineer R&D team drives innovation in split-core design, nanocrystalline core application, and AC/DC leakage detection. Every product undergoes rigorous testing to meet standards like IEC 61869-2 (common industry requirement) and IEEE C57.13 for revenue-grade models. The company’s global supply chain enables consistent export to over 20 countries across Asia, Europe, the Americas, Africa, and Oceania.

Use Cases Across Industries

• Smart Grid & Power Distribution: KCT, DP/HK, and DASN CTs used in switchgear, substation monitoring, and energy metering upgrades.
• Renewable Energy & ESS: KCT, DASN, and RECT for solar inverter monitoring, wind plant revenue metering, and battery storage systems.
• EV Charging Infrastructure: HYCA leakage sensor and KCT split-core CT for safety and power monitoring.
• Data Centers & Telecom: DASN and DX/DM for rack-level power monitoring and PDU integration.
• Industrial Automation: C2/C3 Hall Effect sensor for PV string monitoring, VFD DC bus, and railway traction.
• Infrastructure & Transportation: OCT for overhead line monitoring and FRC for transient current in heavy industry.

Comparison of Key HEYI CT Series

Frequently Asked Questions (FAQ)

Conclusion: Why HEYI ELECTRICAL Stands Out

As a current transformer manufacturer with over a decade of experience, HEYI ELECTRICAL combines technical breadth (10+ product families, up to 10,000 A measurement) with customization depth and global reach. The company’s focus on emerging applications like EV charging, solar ESS, and smart grid aligns with the fastest-growing market segments. For buyers seeking a flexible, quality-driven CT partner, HEYI offers a balanced value proposition of engineering support, production reliability, and competitive lead times. Visit HEYI’s website or contact Bethy Cai at bethy@heyiele.com to discuss your project requirements.