100–2500 kVA SG(B)10 H-Class Insulation Energy-Saving Dry-Type Distribution Transformer

The SG(B)10 H-Class Insulation Energy-Saving and Environmental Protection Dry-Type Distribution Transformer is engineered by JiangSu Dingxin Electric for modern indoor power distribution. Rated for H-class (180°C) thermal insulation, it uses C-class American DuPont NOMEX® paper as the main insulating material, capable of withstanding temperatures up to 220°C.

Compared with the legacy Series 9, the SG(B)10 achieves 15% lower no-load loss, delivering significant energy savings over the entire service life. The transformer is flame-retardant, explosion-resistant, free of harmful gas release, and fully recyclable at end-of-life — making it the ideal solution for safety-critical, eco-sensitive, and noise-sensitive applications.

Model Naming Convention (SG(B)10):

• S — Three phases

• G — Dry type (vs. oil-immersed)

• (B) — Low-pressure foil winding

• 10 — Performance level code (design generation)

• H-Class Insulation System — Rated 180°C with a large insulation design margin, offering excellent heat resistance, strong overload capability, outstanding thermal-shock tolerance, long service life and no-cracking durability.

• High Material Safety — C-class DuPont NOMEX paper (heat-tolerant to 220°C) is flame-retardant, will not aid combustion, will not explode, and will not release harmful gas during a fault.

• Eco-Friendly & Low-Noise Design — High-permeability, high-quality cold-rolled silicon steel sheets with a specially optimized core design deliver operating noise far below national standards. The transformer is fully recyclable at end-of-life with zero pollution.

• Strong Moisture Resistance — Dense NOMEX paper insulation combined with multiple vacuum pressure dipping (VPD) varnish cycles improves sealing and mechanical strength of the winding, providing excellent resistance to mold and humidity.

• Long Service Life — High-grade materials, robust insulation system and optimized thermal design deliver a service life of typically 20+ years under normal operating conditions.

• Low Manufacturing Cost — High temperature tolerance allows a smaller core and lower material usage, reducing both size and weight compared with Series 9 designs, while maintaining full performance.

Standards

IEEE C57.12.01

IEEE C57.12.91

IEC 60076-11/16

IEC 50588-1

UL 5085-1

Regular Service Condition

• Altitude: ≤1000m Indoors

• Maximum Ambient Temperature +40℃

• Maximum daily mean temperature +30℃

• Regular Service Condition

• Maximum annual mean temperature +20℃

• Minimum air temperature -5℃

Transformers that can be operated under the special conditions according to users' requirements.

• Commercial buildings — Office towers, hotels, shopping malls requiring low-noise, fire-safe indoor distribution.

• Hospitals & healthcare facilities — Critical loads where flame-retardant, no-harmful-gas insulation is mandatory.

• Data centers & IT rooms — High reliability and stable voltage for sensitive electronic equipment.

• Airports, metros & railway stations — Public infrastructure with strict safety and noise requirements.

• Industrial plants — Manufacturing facilities, mining and metallurgy requiring robust, overload-tolerant power supply.

• Renewable energy — Solar / wind step-up or auxiliary distribution in distributed generation systems.

• High-rise buildings — Indoor substations where compact size, low noise and fire safety are critical.

• Tunnels, underground facilities & basements — Enclosed environments demanding moisture-resistant, sealed dry-type transformers.

Q1. What is the insulation class of the SG(B)10 dry-type transformer? The SG(B)10 series is rated H-class insulation (180°C), with main insulation made of C-class DuPont NOMEX paper that can withstand up to 220°C.

Q2. What capacity range is available? The SG(B)10 series covers rated capacities from 100 kVA to 2500 kVA, with 16 standard power ratings.

Q3. How energy-efficient is the SG(B)10 compared to the Series 9? Thanks to its high temperature tolerance, the SG(B)10 series achieves 15% lower no-load loss than the Series 9 transformers, significantly reducing operating costs.

Q4. What standards does the SG(B)10 comply with? The SG(B)10 complies with IEEE C57.12.01, IEEE C57.12.91, IEC 60076-11, IEC 60076-16, IEC 50588-1 and UL 5085-1.

Q5. Is the SG(B)10 suitable for humid environments? Yes. The transformer is insulated by dense NOMEX paper products and processed with multiple vacuum pressure dipping varnishes, providing excellent moisture and mold resistance — ideal for humid operating environments.

Q6. Does the SG(B)10 release harmful gas in a fault condition? No. The H-class insulation design with NOMEX paper is flame-retardant, will not aid combustion, and does not release harmful gas — making it safe for indoor and critical installations.

Q7. What is the short-circuit impedance of the SG(B)10? 4.0% for units up to 630 kVA, and 6.0% for units from 800 kVA and above.

Q8. What is the typical service life of the SG(B)10 transformer? With H-class insulation, high-grade silicon steel core and NOMEX paper, the SG(B)10 is designed for a long service life of typically more than 20 years under normal operating conditions.

Need an SG(B)10 H-class dry-type transformer for your project? Contact JiangSu Dingxin Electric Co., Ltd. for datasheets, type-test reports, OEM/ODM service and competitive pricing.