VD4 AF/AF1

Vacuum circuit breaker for steel furnace applications and minimized inrush operations for electrical arc furnace.

Circuit breakers for steel furnace applications

VD4 AF, up to 38 kV, is a medium voltage vacuum circuit breaker for primary distribution based on an innovative actuation system to provide a high quality, reliable and efficient solution for electrical arc furnace (EAF) transformer switching application. VD4 AF is also available with EAF transformer inrush reduction feature, to support your business needs in transformer switching, under the variant VD4 AF1.

Both VD4 AF and VD4 AF1 can perform up to 150,000 mechanical operations granting no downtime for breaker overhaul, thus reducing the total cost of furnace operation.

ABB’s circuit breakers are available for original equipment manufacturers (OEM), panel builders and Engineering, Procurement and Construction (EPCs) partners to incorporate in their own installations or for use in repair, retrofit and upgrade projects.

Product scope

VD4 AF

VD4 AF1

Rated voltage

up to 38 kV

Rated current

up to 2,500 A
3,150 A in fixed version

Rated short circuit current

up to 31.5 kA
40 kA in fixed version

Technology

Vacuum

Operating mechanism

Servomotors

Servomotors with synchronization

Mechanical operations

150,000 overhaul-free operations

150,000 overhaul-free and minimized inrush operations

Monitoring & Diagnostic

Yes

Standards

IEC

Industries

For steel furnaces applications

CUSTOMER BENEFITS

Maximize your productivity

<ul> <li>150,000 operations without refurbishment, including 150,000 minimized inrush operations with VD4-AF1</li> <li>No downtimes for breaker overhaul</li> <li>Fastest replacement with roll on floor draw out solution</li> <li>Tested for shunt reactor current switching according to IEC 62271-110 </li> </ul>

Optimize your investment

<ul> <li>Lowest total cost per operation </li> <li>Reduced spare inventories </li> <li>With advanced monitoring and diagnostics as an option </li> </ul>

Safeguard your personnel and assets

<ul> <li>Embedded basic diagnostics preventing from incorrect operations and hazards </li> <li>Built-in interlocks making it a plug and play solution </li> </ul>

EXPLORE DIGITAL TOOLS & PRODUCT CONFIGURATORS

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Assignment	Application	Description
Product information	3D eCatalogue	A visual tool that allows you to explore ABB medium-voltage switchgear in immersive 3D, configure solutions visually, and make informed decisions with instant access to technical details and application insights.
Product information	Learning	A digital platform that provides training materials, tutorials, and courses to help you build expertise in ABB products and solutions. Accessible resources support continuous learning, professional development, staying current with the latest innovations, and advancing your professional skills.
Configure a product	MV switchgear configurator	The product tool that enables you to create your single-line diagram (SLD), define switchgear configuration details, and instantly access comprehensive technical documentation, making project design and completion faster and more reliable.
Configure a product	MV devices configurator	The user-friendly online tool for selecting and configuring ABB Medium Voltage devices (circuit breakers, contactors, ...) with ease and accuracy, helping you customize solutions to fit your specific technical needs.
Configure a product	Relays Online	The digital platform that offers quick access to ABB protection relay tools, product data, technical documentation, and configuration services, streamlining selection, ordering, and support for Medium Voltage solutions.
Design network/BIM	DOCweb	The ABB online tool for designing electrical MV-LV networks faster and smarter, with real-time calculations, intelligent product selection, automated compliance checks, and instant generation of complete technical documentation, all in just a few clicks.
Design network/BIM	BIMagic	The design tool that simplifies the creation and management of Building Information Modeling (BIM) objects for ABB medium-voltage switchgear, streamlining project planning, integration, and ensuring compliance with industry standards.

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FREQUENTLY ASKED QUESTIONS

VD4-AF and VD4-AF1 are the ABB circuit breakers based on vacuum technology and an innovative actuation system to provide a high quality, reliable and efficient solution for electrical arc furnace (EAF) transformer switching application. VD4-AF and VD4-AF1 can perform 150,000 mechanical operations of the electrical arc furnace (EAF) transformer with minimal maintenance, but only the VD4-AF1 is capable to minimize the related switching transients.

The electrical steel furnace duty cycle requires a high number of open-close operations of the electrical arc furnace (EAF) transformer, with very high frequency. VD4-AF and VD4-AF1 breakers offer a solution for this application with extremely high mechanical life and minimal maintenance. VD4-AF1 has the additional feature of minimizing the switching transient, that will increase the lifetime of the plant components and make the protection of our customers’ assets easier.

VD4-AF and VD4-AF1 are type tested according to IEC 62271-100 Standard.

VD4-AF and VD4-AF1 breakers can perform up to 150,000 mechanical operations with minimal maintenance. The electrical lifetime of the breakers depends on the actual usage.

VD4-AF and VD4-AF1 breakers have the same interface of the standard ABB’s VD4 floor rolling type, so they can replace an exiting VD4 circuit breaker.

VD4-AF and AF1 breakers are released for Unigear ZS3.2 and Powerbloc enclosure