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Siemens 3VA9978-0AA21 Leading Changeover Switch for 3VA4/5/51-55/61-66

Siemens leading changeover switch with HP contacts (14mm) for 3VA4/5/6 breakers.

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ManufacturerSiemens

Part number3VA9978-0AA21

Device Type Leading Changeover Switch

Contact Type Changeover Contacts

Contact Rating HP (14 mm)

Compatible With Siemens 3VA4, 3VA51-55, 3VA61-66 MCCBs

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Leading changeover functionality Type HP (14 mm) contacts For specific Siemens 3VA models Facilitates sequential switching Enhances control logic

Product description

The Siemens 3VA9978-0AA21 is a leading changeover switch accessory equipped with Type HP changeover contacts, measuring 14 mm in width. This component is specifically designed for use with select models of Siemens 3VA4, 3VA51-55, and 3VA61-66 series molded case circuit breakers (MCCBs).

This leading changeover switch is utilized in applications where specific sequential switching or control logic is required, often related to the operation of the main circuit breaker. It can be instrumental in managing power flow, load shedding, or ensuring proper sequencing in complex electrical systems found in industrial plants and large commercial facilities.

Stanlo Automation, a veteran-owned supplier, offers the Siemens 3VA9978-0AA21 to meet your industrial automation needs. We pride ourselves on providing quality surplus parts and dependable service to keep your projects moving forward. Trust Stanlo for your critical component sourcing.

Technical specifications

Device Type	Leading Changeover Switch
Contact Type	Changeover Contacts
Contact Rating	HP (14 mm)
Compatible With	Siemens 3VA4, 3VA51-55, 3VA61-66 MCCBs

Common applications

Industrial control systems

Power distribution management

Load shedding systems

Sequential switching applications

Electrical system sequencing

Compatible systems

Siemens 3VA4 Series MCCBs Siemens 3VA51-55 Series MCCBs Siemens 3VA61-66 Series MCCBs

Also known as

Siemens 3VA9978-0AA21 leading switch Siemens HP leading contacts 3VA4/5/6 leading changeover accessory

Replaces / compatible with

This leading changeover switch is an accessory for specific Siemens 3VA4, 3VA5, and 3VA6 circuit breakers and is not a direct replacement for other components.

Technical note

Expert tip

The 14 mm HP contacts of the 3VA9978-0AA21 are designed for specific switching requirements and must be correctly installed within the compatible Siemens 3VA4, 3VA51-55, or 3VA61-66 circuit breaker models.

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Frequently asked questions

What is a 'leading changeover switch' in the context of the Siemens 3VA9978-0AA21?

A leading changeover switch, like the Siemens 3VA9978-0AA21, is an accessory that provides contacts that operate in a specific sequence relative to the main circuit breaker's operation. It's used for control and interlocking purposes.