Allen-Bradley 1756-IF8 ControlLogix 8 Point A/I Module

Description 

The Allen-Bradley 1756-IF8 is an analog input module from the ControlLogix family. It provides eight configurable input channels supporting ±10 VDC, 0–10 VDC, 0–5 VDC, and 0–20 mA signal ranges. With up to 16-bit resolution and flexible wiring modes, this module is widely used in industrial automation for connecting transmitters, transducers, and other analog devices.

Technical Specifications 

Information About 1756-IF8

The 1756-IF8 is part of Rockwell Automation’s ControlLogix platform, designed to interface multiple analog signals with a controller. It supports eight input channels that can be wired in single-ended, differential, or high-speed differential modes, allowing optimization for noise immunity, channel count, or faster updates. Conversion resolution varies: ±10 VDC signals are digitized at 15 bits (320 µV/count), while 0–10 VDC, 0–5 VDC, and 0–20 mA inputs use 16-bit resolution (80 µV/count for 5 VDC, 0.32 µA/count for current). The module uses Sigma-Delta conversion, outputting data in integer or IEEE 32-bit floating-point format. Scan times range from 16–488 ms (single-ended) to 5–122 ms (high-speed differential). It includes advanced diagnostics such as over/under-range detection, wire-off detection, process alarms, and real-time sampling. For wiring, it requires a removable terminal block, either 1756-TBCH or 1756-TBSH, with user keying. The module draws 150 mA at 5.1 VDC and 40 mA at 24 VDC, consuming 1.73 W, and provides overvoltage protection up to 30 VDC (voltage mode) and 8 VDC (current mode).

Key Features:

• Design: 8-channel analog input module for ControlLogix PAC systems.
• Input Ranges: Configurable for ±10 VDC, 0–10 VDC, 0–5 VDC, or 0–20 mA.
• Resolution: 15–16 bit resolution depending on input type for precise signal acquisition.
• Wiring Modes: Supports single-ended, differential, and high-speed differential wiring.
• Performance: Scan times from 5 ms to 488 ms depending on mode.
• Diagnostics: Over/under-range detection, wire-off detection, process and rate alarms.
• Connectivity: Requires 1756-TBCH or 1756-TBSH removable terminal block.
• Durability: Operates in 0–60 °C environments with real-time sampling and filtering.

The 1756-IF8 delivers high accuracy, flexibility, and reliability for analog signal acquisition in ControlLogix automation systems.

Manufacturer information

Allen-Bradley, a brand of Rockwell Automation, specializes in manufacturing industrial automation equipment. The product range includes programmable logic controllers (PLCs), motion control systems, safety devices, motor control equipment, automation software, and HMI panels. Allen-Bradley products are known for their reliability and integration with other systems.