Application Scenarios

In a pharmaceutical plant’s DCS cabinet, hundreds of 4-20mA sensor signals from the clean room need to be routed to S800 I/O cards. The TB815​ is installed as the central patch panel: field cables terminate on one side, while pre-fabricated harnesses connect the other side directly to the I/O modules. When a pressure transmitter needs calibration, a technician can easily isolate and test the loop at the TB815‘s test points without disturbing the DCS backplane wiring, ensuring zero downtime during maintenance.

 

Parameter

Main Parameters	Value/Description
ABB Order Number​	3BSE013204R1​
Functional Designation​	TB815 Interconnection Unit​
Compatible Systems​	ABB Advant OCS, S800 I/O, Modulebus Networks
Included Component​	1x TB807 Modulebus Terminator​ (critical for bus termination)
Primary Function​	Modulebus Electrical & Optical Interconnection
Redundancy Support​	Yes (Coordinates dual CI820 Communication Interfaces)
Mounting​	DIN Rail (35 mm)
Dimensions (HxWxD)​	250 x 50 x 90 mm
Operating Voltage​	24 V DC (via connected modules)
Operating Temperature​	0°C to +60°C (industrial grade)
Certifications​	CE, UL508, ATEX Zone 2 (for hazardous areas)

 

 

Technical Principles and Innovative Values

• Innovation Point 1: Unified Modulebus Backbone.​ The TB815​ replaces point-to-point wiring with a structured bus architecture. It consolidates the Modulebus​ (the internal communication highway of ABB systems) into a single, managed interconnection point. This design ensures consistent impedance matching and reduces signal reflection, which is critical for maintaining data integrity in high-speed control networks spanning hundreds of meters.
• Innovation Point 2: Dual-Channel Redundancy Coordination.​ A key innovation is its ability to seamlessly interconnect dual CI820​ Fieldbus Communication Interface modules. The TB815​ manages the electrical and optical pathways that allow a primary and backup CI820 to operate in hot-standby mode. If the primary module fails, the TB815‘s passive design ensures the backup module takes over without packet loss, achieving high availability for critical processes like boiler protection or safety shutdown systems.
• Innovation Point 3: Maintenance-Optimized Physical Design.​ Unlike simple terminal blocks, the TB815​ is engineered for serviceability. It provides clear labeling strips, dedicated test points for each signal loop, and fuse holders. This transforms the control cabinet from a “black box” into a serviceable asset, allowing technicians to perform calibration and fault finding without disassembling the entire rack, drastically reducing Mean Time To Repair (MTTR).

 

Application Cases and Industry Value

• Case 1: Power Plant DCS Modernization.​ A coal-fired power plant upgraded its legacy ABB Advant system. The existing wiring was chaotic, leading to intermittent communication faults on the Modulebus. By installing TB815​ units as standardized wiring hubs, the plant organized all field instrument signals (temperature, pressure) and provided a clear demarcation point between the field and the controller. This reduced signal noise-related faults by over 60% and cut the time to troubleshoot a faulty analog input from hours to minutes.
• Case 2: Oil & Gas High-Availability S800 Rack.​ An offshore platform required a fault-tolerant control system for its gas compression skids. The engineering team deployed an S800 I/O rack with dual CI820​ modules for redundancy. The TB815​ was the critical component that physically interconnected the two CI820s and the Modulebus trunk. During a simulated lightning surge that took down the primary CI820, the system automatically failed over to the backup via the TB815‘s pathways, preventing a costly process shutdown and demonstrating its value in SIL-rated safety systems.