Product Overview
The ABB TB521-ETH (1SAP112100R0270) is a terminal base unit designed for the ABB AC500 V2 programmable logic controller (PLC) platform. It provides the mechanical mounting structure, electrical connection interface, and communication expansion capability required for building flexible industrial automation systems. The TB521-ETH is mainly used to connect AC500 processor modules with communication modules, enabling efficient data exchange between PLC systems and external industrial devices.
As an important component of the AC500 automation family, the TB521-ETH integrates an Ethernet interface and supports two communication module slots. It allows engineers to expand PLC communication functions according to different application requirements, making it suitable for distributed control systems, machine automation, and process control applications.
The compact design of the TB521-ETH helps reduce cabinet space requirements while maintaining reliable connectivity between CPUs, communication modules, and field devices.
Technical Specifications
| Parameter |
Description |
| Manufacturer |
ABB |
| Model |
TB521-ETH |
| Product ID |
1SAP112100R0270 |
| Product Type |
Terminal Base |
| PLC Platform |
ABB AC500 V2 |
| Communication Module Slots |
2 slots |
| Ethernet Interface |
Integrated Ethernet interface |
| Serial Interfaces |
RS232 / RS485 |
| Communication Connection |
RJ45, D-SUB, terminal connections |
| Supply Voltage |
24 V DC |
| Protection Degree |
IP20 |
| Operating Temperature |
0 to +60 °C |
| Storage Temperature |
-40 to +70 °C |
| Mounting Type |
DIN rail / panel mounting |
| Net Weight |
Approx. 0.186 kg |
| Dimensions |
123.5 × 135 × 28 mm |
Product Function and Design Concept
The ABB TB521-ETH acts as the connection foundation between an AC500 processor module and additional communication components. Unlike a standard PLC mounting accessory, it provides integrated communication interfaces that allow the controller to connect directly with industrial networks and serial devices.
The terminal base performs several important functions:
- Provides physical mounting for AC500 CPU modules
- Supplies electrical connections between CPU and communication modules
- Enables Ethernet-based industrial communication
- Supports RS232 and RS485 serial communication
- Provides expansion capability through communication module slots
By combining mechanical support and communication functions in one compact unit, the TB521-ETH simplifies PLC system design and reduces installation complexity.
Key Features
Flexible Communication Expansion
The TB521-ETH provides two dedicated communication module slots, allowing users to expand the AC500 PLC system according to application requirements. Engineers can add different communication modules to support various industrial networks and device connections.
Integrated Ethernet Connectivity
The built-in Ethernet interface allows direct connection between the PLC system and industrial networks. This capability supports modern automation architectures requiring fast communication between controllers, supervisory systems, engineering computers, and other automation equipment.
Support for Serial Communication
In addition to Ethernet communication, the TB521-ETH includes RS232 and RS485 interfaces. These interfaces provide compatibility with various industrial devices such as sensors, instruments, drives, operator panels, and legacy automation equipment.
Compact and Modular Structure
The terminal base adopts a compact modular design optimized for ABB AC500 systems. Its small footprint helps save control cabinet space while allowing convenient installation and replacement.
Reliable Industrial Performance
Designed for industrial environments, the TB521-ETH provides stable operation with a robust housing structure and IP20 protection. It is suitable for continuous automation applications where reliable communication is required.
Structure and Components
The ABB TB521-ETH consists of several functional sections that work together to provide a complete PLC connection platform.
CPU Mounting Interface
The upper mounting area is designed for installation of compatible ABB AC500 processor modules. It provides mechanical positioning and electrical connection between the CPU and terminal base.
Communication Expansion Slots
The terminal base includes two communication module slots. These slots allow additional communication functions to be integrated into the PLC system without replacing the main processor.
Ethernet Communication Interface
The Ethernet interface provides network connectivity for PLC communication, programming, monitoring, and integration with higher-level automation systems.
Serial Communication Ports
The RS232/RS485 interfaces support connection with various external devices. These ports are especially useful for applications requiring communication with existing industrial equipment.
Terminal Connection Area
The terminal section provides wiring points for power supply and communication connections, allowing straightforward field installation.
System Compatibility
The ABB TB521-ETH is specifically designed for the ABB AC500 V2 PLC family and works together with compatible CPU modules and communication modules to create scalable automation solutions.
Its modular architecture allows users to expand communication capabilities without changing the complete PLC system, making it a practical choice for both new installations and existing AC500 system maintenance.
Product Summary
The ABB TB521-ETH AC500 V2 Terminal Base is a reliable and flexible PLC expansion component designed for industrial automation applications. With two communication module slots, integrated Ethernet connectivity, RS232/RS485 interfaces, and a compact modular structure, it provides an efficient foundation for building advanced AC500 control systems.
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