The Siemens 3RH2921-1DA11 Lateral Auxiliary Contact Block is a high-quality industrial accessory designed to expand the auxiliary contact capacity of Siemens contactors and control relays. As part of the trusted Siemens SIRIUS 3RH29 accessory range, the 3RH2921-1DA11 enables engineers, panel builders, OEMs, and maintenance professionals to add additional control, signaling, monitoring, and interlocking functions without increasing control panel complexity. Featuring a 1 Normally Open (1NO) and 1 Normally Closed (1NC) contact configuration, this side-mounted auxiliary contact block provides the flexibility required in modern industrial automation systems.
In industrial control environments, auxiliary contacts play a crucial role in feedback signaling, PLC interfacing, status indication, electrical interlocking, alarm systems, and machine sequencing. The Siemens 3RH2921-1DA11 Auxiliary Contact Block offers a practical solution for expanding existing control circuits while maintaining the reliability and performance associated with Siemens industrial products. By adding one NO and one NC auxiliary contact, users can increase functionality without requiring additional relays or control devices.
The 3RH2921-1DA11 is designed as a laterally mountable auxiliary switch block, allowing installation on the left or right side of compatible Siemens contactors and contactor relays. Its snap-on design ensures quick and tool-free installation, reducing assembly time and simplifying maintenance procedures. This compact side-mounting arrangement helps optimize panel space while preserving easy access for wiring and servicing.
One of the major advantages of the Siemens 3RH2921-1DA11 is its versatile 1NO + 1NC contact arrangement. This combination enables both signaling and interlocking functions within a single accessory. The normally open contact can be used for indication, PLC input signals, or control logic, while the normally closed contact is ideal for safety interlocks, fault signaling, and protective control functions. This flexibility makes the device suitable for motor starters, machine tools, packaging equipment, conveyor systems, HVAC installations, and industrial process automation.
The auxiliary contact block is equipped with robust screw terminal connections, ensuring secure wiring and dependable electrical performance even in demanding industrial environments. Screw terminals are preferred by many control panel manufacturers and maintenance professionals due to their reliability, ease of installation, and long-term durability. The design helps maintain stable electrical connections in environments subject to vibration and continuous operation.
Designed according to Siemens' modular SIRIUS system concept, the 3RH2921-1DA11 Auxiliary Contact Block is compatible with selected Siemens 3RT contactors and 3RH contactor relays. The modular design allows users to customize control functions according to application requirements while maintaining system consistency and reducing spare parts inventory.
Built for industrial reliability, the Siemens SIRIUS 3RH2921-1DA11 offers excellent mechanical durability and a long operational life. The auxiliary block is designed for frequent switching operations and supports reliable performance throughout millions of switching cycles. Siemens engineering ensures dependable operation in demanding industrial automation environments where control reliability is critical.
With compact dimensions and side-mount construction, the 3RH2921-1DA11 helps maximize available panel space while expanding control functionality. The device supports industrial standards including IEC 60947 requirements and is suitable for a broad range of low-voltage control applications. Its compact footprint makes it particularly useful in motor control centers, automation panels, and OEM machinery where space optimization is essential.
The Siemens 3RH2921-1DA11 Lateral Auxiliary Contact Block is widely used in manufacturing plants, process industries, infrastructure projects, HVAC systems, water treatment facilities, machine building applications, and industrial automation systems. Whether used for status monitoring, PLC feedback, safety interlocking, or control circuit expansion, this accessory delivers reliable performance and seamless integration into Siemens control systems.
At SBsmart.in, we supply genuine Siemens industrial automation and control products trusted by engineers, contractors, OEMs, and industrial buyers. When you choose the Siemens 3RH2921-1DA11 Auxiliary Contact Block, you receive an authentic Siemens accessory engineered for reliability, easy installation, and long-term industrial performance.
| Specification | Details |
|---|---|
| Product Name | Lateral Auxiliary Contact Block |
| Manufacturer | Siemens |
| Series | SIRIUS 3RH29 |
| Model Number | 3RH2921-1DA11 |
| SKU | 3RH2921-1DA11 |
| Product Type | Auxiliary Switch Block |
| Mounting Position | Lateral (Side Mounted) |
| Contact Configuration | 1NO + 1NC |
| Number of Contacts | 2 |
| Contact Type | Auxiliary Contacts |
| Terminal Type | Screw Terminals |
| Mounting Method | Snap-On |
| Compatible Devices | Siemens 3RT Contactors & 3RH Relays |
| Rated Operational Current AC-15 (230V) | 6 A |
| Rated Insulation Voltage (Ui) | 500 V |
| Surge Voltage Resistance | 6 kV |
| Width | 10 mm |
| Height | 57.4 mm |
| Depth | 66 mm |
| Operating Temperature | -25°C to +60°C |
| Storage Temperature | -55°C to +80°C |
| Mechanical Durability | Up to 10 Million Operations |
| Standards | IEC 60947-4-1, IEC 60947-5-1 |
| Application | Control Circuit Expansion, Monitoring & Interlocking |
| Product Family | Siemens SIRIUS Accessories |
No reviews yet.