Auxiliary contact for circuit breaker | 2NC | 6A | 230VAC | 5ST3012 SIEMENS

Technical Specifications

Manufacturer / Series: Siemens SENTRON

Model: 5ST3012

Accessory Type: Auxiliary Contact

Contact Type: 2 x NC (normally closed)

Compatible with:

Miniature Circuit Breakers: 5SL, 5SY, 5SP

RCBO: 5SU1 (requires connection adapter 5ST3805-1)

RCDs: 5SV

Switches: 5TL1

Mounting: Side-mounted (universal), not factory-integrated

Operating Voltage (AC/DC): 12 V – 400 V

Rated Insulation Voltage: 440 V

Surge Withstand Voltage: 4 kV

Control Voltage: AC/DC

Protection Class: IP20

Electrical Durability: ~10,000 cycles

Operating Temperature: -25 °C to +55 °C

Storage Temperature: down to -40 °C

Dimensions: 90 x 9 x 70 mm

Modular Width: 0.5 module

Weight: 63 g

Terminal Torque: up to 1 N·m

Wire Cross-Section: 0.5–2.5 mm² / AWG 24–12

Compliance Standards: IEC/EN 60947-5-1; IEC/EN 62019

Environmental Declaration (EPD): Yes

CO₂ Footprint: 4.1 kg CO₂ equivalent (entire lifecycle)

Functions:

Dual NC contact: enables integration of two separate signals or control functions

Suitable for automation, alarm, and visualization systems

Easy installation: clips next to main switch without additional tools

Universally compatible with SENTRON series protection devices

Applications:

Electrical distribution boards (residential, commercial, industrial)

Alarm system solutions

Building management systems (BMS)

Control system status indication (e.g., when circuit is off)

Remote status reporting via controller or PLC

Pros:

Universal – fits many Siemens models

Quick and tool-free installation

High Siemens quality and reliability

Suitable for both AC and DC systems

Compact – only 0.5 module wide

Cons:

Cannot be used standalone without a main switch

Requires additional adapter (5ST3805-1) when used with RCBO 5SU1

IP20 rating – unsuitable for dusty or damp environments without enclosure