Siemens 3RH2911-1FA40 SIRIUS Auxiliary Switch 4NO 690V

The Siemens 3RH2911-1FA40 is a SIRIUS front-mounting auxiliary switch with 4 normally open (NO) instantaneous contacts and screw terminals. It snaps onto the front of SIRIUS 3RT2 contactors and 3RH2 contactor relays to expand control circuit capability without modifying the main device. Rated insulation voltage is 690 V AC and surge voltage resistance is 6 kV.

Technical specifications:

• MLFB: 3RH2911-1FA40
• Manufacturer: Siemens
• Product line: SIRIUS
• Product type designation: 3RH29
• Contact arrangement: 4 NO instantaneous (0 NC, 0 CO)
• Insulation voltage: 690 V AC (pollution degree 3)
• Surge voltage resistance: 6 kV
• Operational current at AC-12 (24 V / 230 V): 10 A
• Operational current at AC-15 (24 V / 230 V): 6 A; at 690 V: 1 A
• IP rating (front): IP20
• Mechanical service life: 10,000,000 operating cycles
• Electrical endurance at AC-15 (230 V): 200,000 operating cycles
• Ambient temperature during operation: -25 ... +60 °C
• Mounting: snap-on, front
• Terminals: screw-type
• Conductor cross-section: 0.5 ... 2.5 mm² (solid, stranded, finely stranded with core end)
• AWG conductor: 20 ... 14
• Dimensions (W x H x D): 36 x 37.5 x 43.7 mm
• Net weight: 57 g
• Compatible with: 3RT2.1, 3RT2.2, 3RT2.3, 3RT2.4, 3RH2

Features and benefits:

• Snap-on front mounting enables quick installation and removal on 3RT2 contactors and 3RH2 contactor relays
• Mirror contact function per IEC 60947-4-1 (with 3RT2) supports safety-relevant monitoring circuits
• Positively driven operation per IEC 60947-5-1 ensures reliable contact state indication
• Contact reliability of 1 faulty switching per 100 million operations (17 V, 1 mA) suits low-level PLC signal circuits
• Mechanical service life of 10,000,000 cycles reduces maintenance frequency in high-cycle applications

Applications:

• Control circuit expansion and auxiliary signaling on 3RT2 motor contactors
• Status feedback and interlocking in motor control center panels
• Safety circuit monitoring using the mirror contact function with 3RT2 devices
• Low-level digital input signals (17 V, 1 mA) for PLC and automation controllers

Compliant with IEC 60947-4-1 (mirror contact) and IEC 60947-5-1 (positively driven operation). Part of the Siemens SIRIUS 3RH29 range.

Also known as: Siemens 3RH2911-1FA40, SIRIUS 3RH29 front auxiliary switch, 4NO front-mount auxiliary contact block.