Siemens 3RV1901-1A 1A Switch, Auxiliary Switch, Normally Open, Normally Closed | AmpState

The Siemens 3RV1901-1A is a compact auxiliary switch designed for reliable manual control and precise signaling within Siemens automation systems. Featuring a Normally Open (NO) and Normally Closed (NC) contact configuration, this device delivers dual-state signaling in a single, space-saving package. Its 1 NO / 1 NC setup and 1 A rating make it ideal for low-current control circuits, feedback loops, and interlock logic—perfect for panel retrofit work where keeping the exact part number simplifies maintenance records.

Why this auxiliary switch stands out

• Dual-state signaling: NO and NC contacts provide complementary signals, enabling reliable state detection for PLC inputs and control logic.
• Retrofit-ready: Maintaining the same Siemens part number (3RV1901-1A) streamlines spare-part management and minimizes rewiring during replacements.
• Compact, durable design: Built for panel-mounted applications where space is at a premium, without sacrificing dependable operation in routine control tasks.
• Specifically for control circuits: The 1 A rating is optimized for signaling, interlocks, and auxiliary control—not for heavy motor loads, helping extend service life in appropriate applications.

Specifications at a glance

• Manufacturer: Siemens
• Part number: 3RV1901-1A
• Product type: Auxiliary switch
• Contact configuration: 1 NO / 1 NC
• Amperage rating: 1 A
• Application: Manual control and switching functions in control panels and automation circuits

Ideal use cases

• Maintenance engineers replacing worn auxiliary contacts in Siemens panels while preserving the original part number for documentation continuity.
• Control panel designers needing a compact dual-contact switch to provide clear signaling and interlock feedback for PLCs and safety circuits.
• OEMs integrating a proven Siemens auxiliary contact into new equipment where reliable NO/NC signaling is required without high load currents.

Practical installation tips

• Before replacing, confirm that the NO and NC contacts align with your circuit diagram and PLC input logic.
• Wire the NO contact to indicate an active state and the NC contact to indicate an inactive state, ensuring clean, unambiguous signaling.
• Use this switch for low-current control and signaling paths; avoid relying on it for primary power switching to protect longevity and performance.
• Keep a spare 3RV1901-1A on hand for planned maintenance to minimize downtime during panel retrofits or service events.

AmpState stocks the Siemens 3RV1901-1A, offering dependable support to verify compatibility and fast shipping for retrofit and maintenance projects. With this auxiliary switch, you gain a reliable, part-number-consistent solution that keeps your control system’s signaling precise and your spare parts inventory streamlined.