Siemens 3TK2824-1BB40 Safety Relay Module 24VDC

Siemens 3TK2824-1BB40 is a SIRIUS safety relay module designed for DIN-rail mounting in control cabinets, powered by a 24 V DC coil. The module implements relay release circuits (RC) and provides two instantaneous normally open contacts (2 NO) with no normally closed contacts, all in a 22.5 mm-wide housing with screw-terminal connections for secure wiring. As a basic safety device, it supports AUTOSTART and achieves safety performance up to SIL 1 and PL c, making it suitable for simple safety circuits such as emergency-stop interlocks, safety gates, and interfacing with safety light curtains in machinery control. This Siemens part is part of the SIRIUS family and is commonly used to monitor safety devices and ensure a safe shutdown sequence; Siemens notes that 3TK2824-1BB40 is discontinued, with recommended successors including 3SK1111-1AB30 or 3SK1211-1BB40 for newer installations or replacements.