Siemens 5st3020-2 Fault Signal Contact 2-pole Mcb

Product Description

The SIEMENS 5st3020-2 is a 2-pole fault signal contact designed for use with Sentron-series miniature circuit breakers. It provides electrical feedback on breaker trip events by converting a mechanical fault condition into a monitored signal output through its 1NC-1NO contact configuration. Rated at 400/230 V AC, the unit supports both alarm and acknowledgment functions when paired with MCBs equipped with a test and acknowledge button. Licensed electricians and panel builders typically install this accessory during switchgear assembly or control panel construction where breaker-status monitoring is required.

This fault signal contact is suited for residential, commercial, and light industrial electrical distribution panels. It attaches directly to compatible Siemens miniature circuit breakers in the 5SL, 5SY, and 5SP families, enabling integration with building automation, alarm, or monitoring systems. Typical installations include distribution boards where remote fault indication or supervised tripping is specified by design or code. The compact form factor keeps panel footprint minimal even in dense breaker arrangements.

Key Features

• 2-pole fault signal contact with 1NC-1NO contact arrangement for simultaneous alarm and status monitoring
• Rated at 400/230 V AC for broad compatibility with standard European and IEC-rated distribution systems
• Compatible with MCBs featuring a test and acknowledge button for functional testing of the alarm circuit
• Compact dimensions allow installation in tight DIN-rail panel assemblies without adding significant depth
• Part of the Siemens Sentron 5ST3 accessory series for consistent system integration

Compatibility

Designed for direct mounting with the Siemens 5SL, 5SY, and 5SP series miniature circuit breakers. Compatible with MCBs equipped with a test and acknowledge button.

Installation Notes

Installation should be performed by a licensed electrician in accordance with applicable NEC or IEC wiring standards. De-energize the panel and verify absence of voltage before attaching or removing any breaker accessory. Snap the fault signal contact onto the designated accessory port of the MCB per the breaker manufacturer assembly sequence. Verify contact operation using the MCB test button after installation before returning the panel to service.

Technical Specifications

• Type: 2-Pole Fault Signal Contact
• Contact Configuration: 1NC-1NO
• Voltage Rating: 400/230 V AC
• Height: 3.54 inches
• Width: 0.35 inches
• Depth: 2.76 inches
• Manufacturer Series: Sentron 5ST3

Standard Information

• Brand: SIEMENS
• Manufacturer Part Number: 5st3020-2