ABB IMASI02 Analog Input Module

Overview

The Analog Slave Input Module (IMASI02) inputs 15 channels of analog signals to the Multi-Function 

Processor (IMMFP01/02) or Network 90 Multi-Function Controllers. It is a dedicated slave module that 

connects field equipment and Bailey smart transmitters to the master modules in the Infi 90/Network 

90 System.

The slave also provides a signal path from an Infi 90 operator interface such as Operator Interface 

Station (OIS), or Configuration and Tuning Terminal (CTT) to the Bailey Controls smart transmitters. 

The OIS or CTT connects to the Bailey Controls smart transmitters through the MFP and the ASI. See 

Figure 1-1 for Infi 90 communication levels.

Core Functionality

1.Primary Role: Analog Signal Interface for Infi 90 System

The Analog Slave Input Module (IMASI02) acts as a dedicated interface for the Infi 90 Process 

Management System, with its core function being to acquire and transmit field-side signals. It collects 

fifteen independent process field signals and feeds them into the Infi 90 system—these analog inputs 

serve as critical data sources for the Multi-Function Processor Module (MFP), which uses the signals 

to monitor real-time process conditions and execute control actions .

2. Secondary Role: Command Transmission to Smart Transmitters

Beyond signal acquisition, the IMASI02 also functions as a communication bridge for operating 

commands. It receives control commands from two key sources—either the MFP (central controller of 

the Infi 90 system) or the hand-held Smart Transmitter Terminal (STT)—and transmits these 

commands to Bailey Controls smart transmitters. This ensures seamless coordination between the Infi 

90 system’s control logic (via MFP) or on-site manual operations (via STT) and the field’s smart 

transmitters .

ABB Bailey INFI 90 Series: System Structure & Key Components

The ABB Bailey INFI 90 series is a modular distributed process control system (DCS) tailored for 

industrial automation and safety-critical scenarios, featuring a hierarchical architecture that connects 

field equipment, slave modules, master controllers, and operator interfaces. At its core, the system 

relies on master-slave communication to enable process monitoring and control: the Multi-Function 

Processor (MFP: IMMFP01/02) and Network 90 Multi-Function Controllers serve as central master 

units, while the IMASI02 (Analog Slave Input Module) acts as a dedicated slave component that 

inputs 15 channels of analog signals from field devices (e.g., sensors, Bailey smart transmitters) to the 

master controllers. Critical supporting components include termination devices (NTAI05 Termination 

Unit, NIAI04 Termination Module) that configure and route field signals to the IMASI02 via specialized 

cables (NKTU01, NKTM01), and the Slave Expander Bus (a backplane-mounted parallel bus in the 

Module Mounting Unit/MMU) that enables real-time data exchange between the IMASI02 and MFP. 

Operator interfaces like the Operator Interface Station (OIS), Configuration and Tuning Terminal (CTT), 

and Smart Transmitter Terminal (STT) further integrate with the system—allowing users to configure 

the MFP (via FC 132/133), send commands to smart transmitters through the IMASI02, and monitor 

process status, while the Controlway and INFI-NET/Plant Loop provide redundant, plant-wide 

communication for seamless scalability.