VD4 AF/AF1

Vacuum circuit breaker for steel furnace applications and Inrush-free 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 extremely low inrush, 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 

 

 

up to 38 kV 

 

 

Rated current

 

 

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

 

 

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 

 

 

up to 31.5 kA 
40 kA in fixed version 

 

 

Technology 

 

 

Vacuum 

 

 

Vacuum 

 

 

Operating mechanism 

 

 

Servomotors 

 

 

Servomotors with synchronization 

 

 

 

Mechanical operations 

 

 

 

150,000 maintenance-free operations 

 

 

150,000 maintenance-free and inrush-free operations 

 

 

Monitoring & Diagnostic

 

 

Yes 

 

 

Yes 

 

 

Standards 

 

 

IEC 

 

 

IEC 

 

 

Industries 

 

 

For steel furnaces applications 

 

 

For steel furnaces applications 

 

Customer benefits

Maximize your productivity

<ul> <li>150,000 operations without refurbishment, including 150,000 inrush free 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&nbsp;</li> </ul>

Optimize your investment

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

Safeguard your personnel and assets

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

Related offering

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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