Contactor Relays (Auxiliary Contactors), 3RH2 (S00) with “Mechanically linked contact elements”, DC Coil@ - 3RH2131-1BB408K

Product Description

Siemens 3RH2131-1BB408K Auxiliary Contactor Relay – 24V DC Control Relay with Mechanically Linked Contact Elements

The Siemens 3RH2131-1BB408K Auxiliary Contactor Relay is a high-performance industrial control device engineered for reliable switching, signaling, interlocking, and automation applications. As part of the trusted Siemens SIRIUS 3RH2 Series, this auxiliary contactor is specifically designed for modern control systems requiring dependable auxiliary switching and enhanced operational safety. Equipped with 3 Normally Open (3NO) contacts, 1 Normally Closed (1NC) contact, a 24V DC control coil, and mechanically linked contact elements, the 3RH2131-1BB408K provides exceptional reliability for industrial automation, machine control, PLC interfaces, and process control applications.

One of the standout features of the Siemens 3RH2131-1BB408K is its mechanically linked contact system. This design ensures that normally open and normally closed contacts cannot simultaneously indicate conflicting states. Mechanically linked contacts are particularly important in safety-related circuits, monitoring systems, and interlocking applications where accurate contact status is essential for safe machine operation. This feature improves system integrity and helps engineers comply with modern industrial safety requirements.

The 3RH2131-1BB408K Auxiliary Contactor Relay incorporates a versatile 3NO + 1NC contact configuration, providing flexible switching capabilities for a wide range of control tasks. The normally open contacts can be used for PLC inputs, signaling functions, motor starter logic, automation commands, and machine sequencing. The normally closed contact supports interlocking circuits, fault monitoring, emergency shutdown logic, and status indication systems. This flexibility makes the relay suitable for manufacturing facilities, process industries, packaging machinery, conveyor systems, HVAC controls, water treatment plants, and energy management systems.

Designed in the compact S00 frame size, the Siemens SIRIUS 3RH2131-1BB408K provides excellent space efficiency for modern control panels and automation cabinets. Despite its compact dimensions, the device delivers industrial-grade performance with a rated operational current of up to 10A AC-15 at 230V, making it suitable for demanding switching applications. The compact footprint allows engineers to maximize panel space while maintaining easy access for installation and maintenance.

The relay operates using a 24V DC control coil, making it ideal for PLC-controlled systems and industrial automation architectures that rely on DC control voltages. Siemens engineering ensures stable operation within a wide voltage tolerance range, helping maintain reliable performance even under varying supply conditions. The coil consumes approximately 4W, providing efficient operation while maintaining strong switching performance.

The Siemens 3RH2131-1BB408K utilizes durable screw terminal connections, which are widely preferred in industrial control systems due to their secure conductor retention and long-term reliability. Screw terminals provide excellent resistance to vibration and mechanical stress, ensuring stable electrical performance in demanding industrial environments. This connection technology also simplifies installation and future maintenance activities.

Built according to Siemens' proven SIRIUS modular system philosophy, the 3RH2131-1BB408K Auxiliary Contactor supports compatibility with a wide range of accessories, including auxiliary contact blocks, surge suppressors, and mounting accessories. This modularity enables engineers and panel builders to customize control systems according to specific application requirements while maintaining standardized Siemens components throughout the installation.

The relay is engineered for exceptional durability and long service life. Siemens specifies a mechanical endurance of up to 30 million operating cycles, making the 3RH2131-1BB408K an excellent choice for high-duty industrial applications. With a rated insulation voltage of 690V, impulse withstand voltage of 6kV, and compliance with international industrial standards, the relay delivers dependable operation even in electrically demanding environments.

Industrial professionals trust the Siemens 3RH2131-1BB408K Auxiliary Contactor Relay for machine automation, process control, PLC interfacing, control panel construction, motor starter circuits, industrial signaling, and interlocking applications. Its combination of mechanically linked contacts, compact design, high durability, and Siemens engineering excellence makes it a preferred solution for modern industrial automation systems.

At SBsmart.in, we provide genuine Siemens industrial automation products trusted by engineers, OEMs, panel builders, system integrators, and industrial buyers throughout India. When you purchase the Siemens 3RH2131-1BB408K, you receive an authentic Siemens SIRIUS auxiliary contactor designed for superior performance, operational safety, and long-term reliability.