Siemens 3VA99780AA12 3A 300V Switch, Auxiliary Switch | AmpState

Siemens 3VA99780AA12 Auxiliary Switch is built for everyday electrical work, delivering reliable manual control and precise switching in compact control panels. With a 3 A current rating at 300 V, this auxiliary contact provides clear signaling and dependable operation where it matters most in panel setups, maintenance tasks, and repair rounds.

• Manufacturer: Siemens
• Part Number: 3VA99780AA12
• Product Type: Auxiliary Switch
• Amperage: 3 A
• Voltage: 300 V
• Applications: Manual control, switching functions, control-panel signaling

What makes this auxiliary switch stand out

In environments where a direct part-number match matters for sourcing, stocking, and quick replacement, the 3VA99780AA12 from Siemens delivers a precise fit with predictable performance. Its dedicated auxiliary function supports status indication and control signaling without imposing on the main circuit, helping you keep critical systems transparent and responsive.

Ideal use cases

• Maintenance crews updating or repairing control panels where a dedicated auxiliary contact is required
• Panel builders integrating signaling for PLC inputs, interlocks, or indicator circuits
• Spare inventory for service fleets that rely on exact part numbers for rapid replacements

Why it matters for your project

Having the right auxiliary switch reduces downtime and simplifies ordering. The Siemens 3VA99780AA12 provides a stable, trustworthy control signal in a compact form, making it a practical choice for panel-level automation, motor control centers, and distributed control systems that need reliable auxiliary feedback.

Compatibility and support

Available from AmpState, this part is designed for straightforward direct-part-number replacement in compatible Siemens installations. If you’re unsure about fit, AmpState can help confirm compatibility and ensure you’ve chosen the exact auxiliary switch your system requires. Need help matching a part number or confirming compatibility? Message us and we’ll help you confirm fit.