Siemens SIRIUS 3RH2 Auxiliary Switch Block, 4 NO Contacts, Front Mounting, Screw Terminals, 3RH2911-1GA40

For control circuits that demand reliable signal multiplication, the Siemens 3RH2911-1GA40 auxiliary switch block stands apart with its 4 normally open (NO) contacts and front-mounting design tailored for SIRIUS 3RT2 contactors and 3RH2 control relays. Unlike generic add-on blocks, this unit delivers precise switching status feedback with high electrical and mechanical endurance, ensuring long-term stability in industrial environments.

Highlights

• 4 NO contacts for versatile control and signaling tasks
• Front mounting for quick, tool-free snap-on installation
• Screw terminals accept solid and fine-stranded conductors up to 4 mm²
• Rated insulation voltage 690 V, impulse withstand 6 kV
• High durability: 10 million electrical, 30 million mechanical cycles

In daily use

Mounted directly onto the front of a contactor or relay, this block mirrors the main contacts' state, enabling interlocking, status indication, or load control. Its compact footprint preserves panel space, while the screw terminals ensure secure, maintenance-free connections. The IP40 front protection guards against accidental contact, and the wide operating temperature range (-25 to +60 °C) suits harsh industrial settings.

Full specifications

• Product type: Auxiliary switch block
• Series: SIRIUS 3RH2
• Contact configuration: 4 NO (Normally Open)
• Number of poles: 4
• Mounting type: Front mounting
• Compatibility: For 3RT2 contactors, 3RH2 control relays
• Connection type: Screw terminals
• Rated insulation voltage (Ui): 690 V
• Rated impulse withstand voltage (Uimp): 6 kV
• Rated operational current (AC-15, 230 V): 6 A
• Rated operational current (AC-15, 400 V): 3 A
• Rated operational current (DC-13, 24 V): 10 A
• Rated operational current (DC-13, 220 V): 0.3 A
• Conductor cross-section, solid: 0.5 - 4 mm²
• Conductor cross-section, fine-strand with sleeve: 0.5 - 2.5 mm²
• Operating temperature range: -25 to +60 °C
• Degree of protection (front): IP40
• Degree of protection (terminals): IP20
• Electrical durability: 10 million switching cycles
• Mechanical durability: 30 million switching cycles

Final note

Engineered for seamless integration with Siemens SIRIUS modular system, this auxiliary switch block is the dependable choice for expanding control functionality without compromising on performance or safety.