Siemens Auxiliary switch on the front, screw, 1NO+2NC Part number 3RH2911-1HA12

Product Overview

The Siemens auxiliary switch on the front, screw, 1NO+2NC, article number 3RH2911-1HA12, is a front-mounted auxiliary contact block designed to extend the control and signalling capabilities of compatible SIRIUS contactors. This auxiliary switch provides a total of three auxiliary contacts consisting of one normally open (NO) and two normally closed (NC) contacts. It mounts on the front of the contactor and uses screw terminals to ensure secure and reliable wiring in industrial automation and motor control applications.

Key Features

• Auxiliary switch for contactor expansion
• Front-side mounting design
• Contact configuration: 1 normally open (NO) + 2 normally closed (NC)
• Screw terminal connections for secure wiring
• Adds signalling, feedback, and interlocking capability
• Compact design suitable for control cabinet installations
• Industrial-grade construction for reliable operation

Technical Specifications

• Article Number: 3RH2911-1HA12
• Product Type: Front-mounted auxiliary switch
• Contact Configuration: 1 NO + 2 NC
• Mounting Position: Front of compatible contactor
• Terminal Type: Screw terminals
• Function: Auxiliary signalling and control contacts
• Protection Class: IP20 when installed
• Operating Environment: Industrial automation systems

Compliance & Standards

• Designed in accordance with Siemens requirements for auxiliary contact accessories
• Suitable for use in industrial control and automation circuits
• Meets applicable low-voltage switching and safety standards

Applications

The Siemens 3RH2911-1HA12 auxiliary switch is used to provide additional normally open and normally closed contacts for signalling and interlocking in control circuits. Typical applications include PLC input feedback, status indication, safety interlocks, and control logic expansion in motor control panels, automation cabinets, and industrial machinery where front-mounted auxiliary contacts are required.