Three Phase Dry Type Isolation Transformer 10–2500 kVA

Key Specifications

Three Phase Dry Type Isolation Transformer Product Introduction

A three-phase dry-type isolation transformer uses air for insulation and cooling instead of oil, eliminating the risk of fire and oil leakage. It is flame-retardant, explosion-proof and has low operating losses. Equipped with an intelligent temperature control system, it can be installed directly at the load center, making it ideal for modern urban power grids and industrial distribution systems. CHBEB is a professional manufacturer of high-quality dry-type transformers. The main rated parameters are as follows:

• Standard tap changer: ±2×2.5% off-circuit taps. 380 V for aging grids in Africa, 400 V for the Middle East and mainstream African markets, and 480 V for US industrial grids.
• Connection group: Dyn11 or Dy1. Dyn11 follows IEC practice for the Middle East and Africa; Dy1 matches ANSI phase conventions for the US.
• Frequency: 50 Hz or 60 Hz. 50 Hz for municipal grids in the Middle East and Africa; 60 Hz for the US and overseas standby generator sets.
• Short-circuit impedance: 4%, 5.75% or 6%. 4% for conventional distribution in the Middle East and Africa; 5.75% or 6% for US and oilfield sites with higher fault risk.
• No-load loss: ≤ 480 W at 50 Hz, or customized to DOE requirements at 60 Hz. US shipments are recalculated and retested to meet DOE efficiency standards.
• Load loss: ≤ 1700 W at 120°C and 50 Hz, or DOE-specified values at 60 Hz. US orders require recalculation.
• Power frequency withstand voltage: 3 kV/1 min, 4 kV/1 min or UL-specified levels. 3 kV for general African projects, 4 kV for high-standard Middle East clients, and UL-specified levels for US-certified models.
• Insulation class: F or H. Class F for conventional indoor use; Class H for hot and dusty environments such as the Middle East.
• Cooling mode: AN/AF (natural air cooling / forced air cooling), applicable to all markets.

Product Advantages

• Low-loss core: The three-phase core is made of high-grade grain-oriented silicon steel, with the yoke ends coated in a special resin adhesive, ensuring low loss, low noise and stable operation.
• Reliable low-voltage coils: The interlayers of the low-voltage coils are wound with pre-impregnated DMD insulation and cured at high temperature, providing excellent insulation and mechanical strength.
• Vacuum-cast high-voltage coils: The high-voltage coils use a segmented multilayer cylindrical structure with longitudinal air ducts, made by vacuum pressure casting. They offer high mechanical strength, strong short-circuit withstand capability, low partial discharge and resistance to moisture, dust and salt spray.
• Simple, compact design: The neat overall structure makes operation and maintenance easier.

Application Advantages

• Global certification: A single unit can carry both CE and UL certifications, supporting sales in markets worldwide.
• Wide application: Three-phase dry-type isolation transformers are widely used in industrial and civil distribution, especially where fire and explosion protection requirements are strict, such as high-rise buildings, metro stations, hospitals, data centers and other indoor sites.
• Safe and environmentally friendly: Using air and resin instead of oil for insulation and cooling, they are valued for their safety and environmental performance.

Electrical Parameters

Rated Capacity & Voltage Parameters

Insulation & Withstand Voltage Parameters

Loss & Impedance Parameters

Temperature Rise, Cooling & Protection Parameters

Contact Us

Looking for a reliable three-phase dry-type isolation transformer for your project? CHBEB supplies three-phase isolation transformers from 10 kVA to 2500 kVA, with IEC and UL versions, standard designs and customized solutions available. Browse our CHBEB isolation transformers or contact our team today with your voltage, capacity and installation requirements to get a fast quote and professional technical support.