The TB840A (part number 3BSE037760R1) is a redundant cluster module from ABB, designed for high-availability systems. It provides a robust link between two separate AC 800M controllers, enabling bumpless transfer and controller redundancy. This ensures continuous operation and prevents system downtime. The TB840A is ideal for high-end HI series controllers like the PM865.

Technical Specifications

The TB840A module is a passive unit, meaning it does not contain an internal power supply or active electronic components. It functions as a critical connection point, offering a simple yet highly effective design that contributes to system reliability. The key feature of the TB840A is its ability to create a redundant link over a distance of up to 12 meters using two optical cables.