ABB AI845 3BSE023675R1 S800 I/O Analog Input Module

Description

The AI845 with product ID 3BSE023675R1 is an 8-channel analog input module designed for the S800 I/O distributed system architecture. This hardware unit interfaces standard 0 to 20 mA or 4 to 20 mA current signals from field transmitters directly to the central processing controller. It incorporates dedicated HART routing capabilities per channel, enabling bi-directional communication with smart instruments over existing analog loops without altering regular process variable transmission. It provides dual-channel hardware redundancy options when paired with appropriate terminal units, maintaining active signal paths and system availability during single module exceptions.

Features

• Provides 8 single-ended current tracking input channels supporting 0 to 20 mA or 4 to 20 mA signals.
• Integrates channel-by-channel HART pass-through communication for asset management systems.
• Supports hot-swapping and fully redundant configurations for uninterrupted process data acquisition.
• Features integrated diagnostic routines to supervise open-circuit monitoring and out-of-range signal states.
• Utilizes compact electrical termination setups using standard S800 Module Termination Units.

Applications

• High-availability process loop telemetry inside petrochemical refining and power generation units.
• Dual-fault tolerant interface links interfacing safety parameters with distributed control systems.
• Asset management integration utilizing remote HART diagnostic mapping protocols.

Technical Specifications

Connections/Interfaces

Installation Guidelines

• Baseplate Insertion: Verify that the Module Termination Unit (such as TU844 or TU845) is secured onto the DIN rail before engaging the module body. Disconnect primary electrical feeds, align the plastic guide tabs, and apply uniform vertical force until the side retention latches click home.
• Shielding Protocol: Terminate the outer metal mesh of twisted-pair instrument wires using the ground bars situated on the enclosure entry frame. Maintain single-point earth terminations at the control cabinet wall to eliminate low-frequency ground-loop feedback.
• Redundant Configuration: To execute redundant module deployments, both units must reside in an identical, paired-slot termination cluster. Map the master/backup hierarchy inside the control programming software to handle hot-standby functions.
• Cable Separation Routing: Route low-current operational signals in separate wiring ducts isolated from variable speed drives, bulk contactor control blocks, and heavy three-phase power buses by a minimal clear air threshold of 30 cm.