Siemens 3RH1921-2CA01 SIRIUS Auxiliary Switch 1NC Spring for 3RT1

The Siemens 3RH1921-2CA01 is a SIRIUS front-side auxiliary switch with 1 NC instantaneous contact and spring-loaded terminals, designed for snap-on mounting onto 3RT1 series contactors. Insulation voltage is 690 V AC with a surge voltage resistance of 6 kV, and the maximum operational current is 10 A at AC-12 and 1 A at AC-15/690 V.

Technical specifications:

• MLFB: 3RH1921-2CA01
• Manufacturer: Siemens
• Product line: SIRIUS
• Product type: Front-side auxiliary switch
• Contact arrangement: 1 NC instantaneous contact
• Insulation voltage: 690 V AC
• Surge voltage resistance: 6 kV
• Operational current (AC-12, max): 10 A
• Operational current (AC-15, 690 V): 1 A
• Operational current (AC-15, 230 V): 6 A
• IP rating: IP20 (front)
• Mechanical service life: 10,000,000 operating cycles
• Electrical endurance: 200,000 operating cycles (AC-15, 230 V)
• Ambient temperature (operation): -25 to +60 °C
• Ambient temperature (storage): -55 to +80 °C
• Fastening: snap-on mounting
• Terminals: spring-loaded, 0.5 to 2.5 mm²
• AWG range: 20 to 14
• Dimensions (W x H x D): 10 x 38 x 51 mm
• Net weight: 0.017 kg
• Compatible contactors: 3RT10, 3RT12, 3RT145, 3RT146, 3RT147

Features and benefits:

• Snaps directly onto the front of 3RT1 contactors without tools for fast field installation
• Spring-loaded terminals accept 0.5 to 2.5 mm² solid, stranded, or finely stranded conductors
• Mirror contact function per IEC 60947-4-1 when paired with 3RT1 contactors for safety monitoring
• 10,000,000-cycle mechanical service life for long-term panel reliability
• 10 mm narrow width minimises DIN rail space in control cabinets

Applications:

• Safety feedback and interlocking circuits in motor control centres
• Auxiliary signalling on 3RT10, 3RT12, 3RT145, 3RT146, and 3RT147 contactors
• Position feedback in automated machine control panels
• Pilot control circuits in motor starter assemblies

Compliant with IEC 60947-4-1 and IEC 60947-5-1. Part of the Siemens SIRIUS 3RH19 range.

Also known as: Siemens 3RH1921-2CA01, SIRIUS 3RH19 front-side auxiliary contact block, Siemens 1NC spring-terminal auxiliary switch.