Siemens 5ST3020 SENTRON Fault Signal Contact 1NO+1NC 440V

The Siemens 5ST3020 is a SENTRON fault signal contact with a 1 NO + 1 NC contact arrangement, designed to mount on miniature circuit breakers 5SL, 5SY, and 5SP, RCBO 5SU1 (requires handle coupler 5ST3805-1), and RCCB 5SV. It provides an electrical signal when the breaker trips, enabling remote fault monitoring. Rated insulation voltage is 440 V with 4 kV surge voltage resistance.

Technical specifications:

• MLFB: 5ST3020
• Manufacturer: Siemens
• Product line: SENTRON
• Product type: Fault signal contact
• Contact arrangement: 1 NO + 1 NC
• Rated insulation voltage: 440 V
• Surge voltage resistance: 4 kV
• Operating voltage: min 12 V AC/DC, rated 400 V AC
• Operational current (DC): 0.01 A
• Control voltage type: AC/DC
• IP rating: IP20
• Electrical endurance: 10,000 operating cycles (typical)
• Conductor cross-section: 0.5 - 2.5 mm²
• AWG: 24 - 12
• Screw terminal tightening torque: max 0.5 Nm
• Dimensions (WxHxD): 9 x 90 x 70 mm (1 module wide)
• Net weight: 58 g
• Operating temperature: -25°C to +55°C
• Storage temperature: min -40°C
• Standards: IEC/EN 60947-5-1; IEC/EN 62019

Features and benefits:

• 1 NO + 1 NC contacts allow simultaneous normally-open and normally-closed signaling in a single accessory
• Universal mounting - compatible with 5SL, 5SY, 5SP MCBs and 5SU1 RCBO, 5SV RCCB
• AC/DC control voltage from 12 V enables integration with diverse monitoring and alarm systems
• Compact 1-module (9 mm) footprint minimises DIN rail space
• Wide operating temperature range -25°C to +55°C suits demanding installation environments

Applications:

• Remote fault indication in residential and commercial distribution boards using SENTRON MCBs
• Trip status signaling to building management systems or PLCs
• Fault monitoring in RCBO 5SU1 installations (with handle coupler 5ST3805-1)
• Alarm circuits in LV switchgear and industrial control cabinets

Compliant with IEC/EN 60947-5-1 and IEC/EN 62019. Part of the Siemens SENTRON range.

Also known as: Siemens 5ST3020, SENTRON fault signal contact, trip alarm contact for MCB.