# BEST Transformer 40 MVA 34.5 kV / 650V Electric Arc Furnace (EAF) Furnace Transformer

> BEST Transformer 40 MVA 34.5 kV / 650V Electric Arc Furnace (EAF) Furnace Transformer belongs to the Arc & Melting Furnace Transformers (EAF/LF/SAF) category and is rated at 40 MVA with 34.5/0.65 kV primary/secondary voltage. Application: Steel Rolling Mills & Scrap Melting Arc Furnaces. Final ratings must be verified against the manufacturer datasheet.

> SKU: VF-BEST-EAF-40M-345 | Brand: BEST Trafo (Balıkesir Elektromekanik) | Category: Power & Energy Equipment / Transformers / Special Industrial & Process Transformers / Arc & Melting Furnace Transformers (EAF/LF/SAF)

**Voltformer canonical:** https://voltformer.com/product/best-transformer-40-mva-34-5-kv-650v-electric-arc-furnace-eaf-furnace-transformer - markdown version: https://voltformer.com/product/best-transformer-40-mva-34-5-kv-650v-electric-arc-furnace-eaf-furnace-transformer.md

## Overview

BEST Transformer 40 MVA 34.5 kV / 650V Electric Arc Furnace (EAF) Furnace Transformer is intended for Steel Rolling Mills & Scrap Melting Arc Furnaces. Configured electrical data: 40 MVA, 34.5/0.65 kV primary/secondary voltage, 50 Hz, 3-phase, vector group configuration-specific vector group and short-circuit impedance 11.5%. Construction: Copper (Cu-Cu); cooling: OFWF; loss class: Heavy Duty Steel Plant Grade. These values support preliminary engineering selection; verify insulation levels, thermal limits, short-circuit duty, installation conditions and applicable standards against the manufacturer datasheet and the site study.

- **Application:** Steel Rolling Mills & Scrap Melting Arc Furnaces
- **Target industries:** Steel Rolling Mills, Foundries & Smelters
- **Brand:** [BEST Trafo (Balıkesir Elektromekanik)](https://voltformer.com/brand/best-trafo.md) - Turkey's most established transformer manufacturer since 1966; BEST Trafo is the choice for global EPC projects with high-voltage power transformers up to 1000 MVA 525 kV, arc furnace transformers, TE
- **Category:** [Power & Energy Equipment](https://voltformer.com/catalog.md) / **Transformers** / [Special Industrial & Process Transformers](https://voltformer.com/category/special-industrial-process-transformers.md): Arc furnace (EAF), green hydrogen electrolyser, rectifier, traction and mining Ex-proof transformers. / [Arc & Melting Furnace Transformers (EAF/LF/SAF)](https://voltformer.com/category/special-industrial-process-transformers/electric-arc-furnace-transformers.md)

## Technical Specifications

| Property | Value |
|---|---|
| Rated power | 40 MVA |
| Primary / secondary voltage | 34.5 kV / 0.65 kV (±15 tap-changing motorized tap selector) |
| Frequency / phases | 50 Hz / 3-phase - Dyn11 (special copper secondary busbar) |
| Short-circuit impedance (Uk) | 11.5% |
| No-load loss P0 | 28.00 kW |
| Load loss Pk | 210.0 kW |
| Calculated efficiency (power factor = 1) | 99.41% at 100% load; 99.6% at 50% load |
| Loss class | Heavy Duty Steel Plant Grade |
| Windings | Copper (Cu-Cu) - cooling: OFWF - insulation: Class A |
| Temperature rise | 65 K - sound pressure: 70 dB(A) |
| Mass and dimensions | 58000 kg - 5400×3400×4800 mm |
| Enclosure | IP55 - wheel gauge: 1600 mm |
| LI / AC withstand | 170 kV peak / 70 kV rms - partial discharge: 10 pC |
| Environment | -25°C / +40°C; altitude ≤ 1000 m |
| Core steel | CRGO Laser-Treated Grain-Oriented Silicon Steel (23ZDMH85 / Baosteel B23R085) |
| Bushings / terminals | Plug-in Separable Elbow Terminals (Dead-Front) / Porcelain DIN 42531 |

## Standards

- IEC 60076
- IEC 61378
- TS EN 60076

## Accessories

**Included:** OFWF Water Heat Exchanger, Heavy-Duty Tap Changer, Internal Reactor
**Optional:** Online Temperature & Vibration Tracking System

## Official sources

- https://www.besttransformer.com/

- **Source scope:** manufacturer-family
- **Last reviewed:** 2026-09-13

Manufacturer portfolio/family source. Confirm the exact order code, guaranteed ratings and project-specific options against the current OEM datasheet before procurement or an SLD study.

## Pricing & Logistics

- Pricing type: RFQ (Project Engineering) - Indicative range: $460,000 – $540,000 USD
- Delivery time: 2–8 weeks (may vary depending on technical configuration, factory capacity and destination) - Warranty: 36 months
- Compliance candidates: IEC 60076, IEC 61378, TS EN 60076. Verify applicability and conformity against the exact offered model and project jurisdiction.

## RFQ

Request a formal factory quotation via Voltformer RFQ:

```json
POST https://voltformer.com/api/v1/rfq
{"companyName":"Example Energy","email":"procurement@example.com","items":[{"skuOrId":"VF-BEST-EAF-40M-345","quantity":1}]}
```

Full catalog JSON: https://voltformer.com/agent-catalog.json - OpenAPI: https://voltformer.com/openapi.json