ABB Bailey IMRAI12 – Analog Input Module for Process Signals

The ABB Bailey IMRAI12 converts field analog signals into digital data for controllers. This module measures 250 mm in depth and 180 mm in height. It weighs approximately 0.85 kg, so handling remains manageable during installation. You will find sixteen differential input channels on this device.

Internal Board Architecture and Signal Flow

This analog input module contains three separate circuit boards inside its metal housing. One board handles input multiplexing, while another performs analog-to-digital conversion. The third board manages communication with the main backplane. The ABB Bailey IMRAI12 uses a 16-bit ADC for each input channel. This converter provides a resolution of 0.0015 percent of the full scale.

Input Ranges and Field Wiring Connections

You can configure each channel independently for voltage or current signals. Voltage ranges include 0 to 5V, 0 to 10V, and ±10V DC. Current ranges include 0 to 20 mA and 4 to 20 mA. The ABB Bailey IMRAI12 provides 32 screw terminals on its front panel. These terminals accept wire gauges from 24 AWG to 18 AWG comfortably.

Energy Storage and Power Consumption

The module stores 470 µF of capacitance across its power filtering circuits. This storage smooths out minor fluctuations on the 24V DC supply rail. The ABB Bailey IMRAI12 draws 250 mA at 24V DC during normal operation. Therefore, total power consumption reaches 6 watts for the entire module. It contains no backup battery, so maintenance requirements stay minimal.

Sampling Performance and Environmental Limits

You can set the sampling rate from 10 Hz up to 500 Hz per channel. The module applies a 50 Hz or 60 Hz digital filter for noise rejection. The ABB Bailey IMRAI12 operates reliably from 0°C to 55°C ambient temperature. It tolerates humidity levels up to 95 percent without condensation problems. You can mount this unit in any standard 19-inch rack or cabinet.

Below is a complete summary of its technical specifications.

The ABB Bailey IMRAI12 replaces older analog cards in Bailey INFI 90 systems seamlessly. You do not need any adapter plates or special configuration tools. This module also supports hot-swapping, so you can replace it without powering down. Consequently, you can maintain uptime while upgrading your analog input capacity.