Description

The ABB TC570 (Ordering No. 3BSE001458R1) is a high-performance Digital Input (DI) Module belonging to the ABB S800 I/O product family. Designed for use with AC 800M controllers and the 800xA system (as well as legacy Advant OCS), this module provides the critical interface between field sensors/switches and the digital control logic.

The TC570 typically features 16 or 32 channels of 24V DC input. It is engineered for high reliability in noisy industrial environments, offering built-in input filtering (to reject electrical noise and contact bounce), short-circuit detection (for external wiring faults), and open-circuit monitoring (depending on configuration). Each channel’s status is clearly indicated by LEDs, facilitating rapid troubleshooting of field devices like limit switches, pressure transmitters (switch output), and emergency stop buttons. The module connects to the S800 backplane via the CEX-Bus, ensuring fast and deterministic data exchange with the controller. Note: Contrary to some misconceptions, this is NOT a Fieldbus Master unit; it is a discrete I/O module for status monitoring.

Application Scenarios

In a combined cycle power plant, the turbine protection system required monitoring of over 50 vibration and temperature switches. The engineering team selected ABB TC570 modules to acquire these critical safety signals. During a startup sequence, one of the lube oil pressure switches failed to close. The TC570 module, configured with a specific input filter time to ignore transient spikes, correctly identified the sustained “Open” state and sent a trip signal to the AC 800M controller within 10ms. The controller immediately initiated a safe shutdown, preventing catastrophic bearing damage. The module’s diagnostic LED allowed maintenance to instantly locate the faulty switch, minimizing downtime.