Allen-Bradley 1771-ILK Isolated Analog Input Module for PLC-5 Systems

Product Overview

When your process demands precise, isolated analog measurements, the Allen-Bradley 1771-ILK delivers. This analog input module is part of the PLC-5 family and provides eight individually isolated 1000-volt differential inputs. With a conformal coating for harsh environments and a 15-bit plus sign resolution, it ensures reliable data acquisition in industrial settings.

Technical Specifications

The 1771-ILK offers versatile signal handling. Its voltage ranges include 0-5 V dc, 1-5 V dc, +/- 5 V dc, 0-10 V dc, and +/- 10 V dc. Current ranges cover 4-20 mA, 0-20 mA, and +/- 20 mA. The module updates all eight channels in 500 ms and uses natural binary or BCD scaling to +/- 9999 data format. Backplane current draw is 1.3 amperes, and no external power is required. Typical AC signal delay (off) is 24 (+/- 10) ms, and typical DC signal delay (off) is 20 (+/- 9) ms.

Industry Applications

This module excels in applications requiring channel-to-channel isolation, such as monitoring multiple sensor signals in chemical processing, power generation, or water treatment plants. The 1000-volt isolation protects sensitive PLC inputs from ground loops and transient voltages. For example, in a refinery, the 1771-ILK can safely interface with temperature transmitters and pressure transducers across different grounding zones.

Installation & Setup

Mount the 1771-ILK in a standard PLC-5 rack using the 1771-WF wiring arm. The module is rack-mountable and includes a status indicator for quick diagnostics. Ensure the backplane current draw of 1.3 amperes is within your system's power budget. No external power supply is needed, simplifying wiring.

Maintenance & Reliability

The conformal coating protects against moisture and contaminants, extending service life in demanding environments. For maximum reliability, inspect the module periodically for signs of corrosion or damage. Follow the manufacturer's guidelines for cleaning and handling. Routine verification of input signals against expected values helps detect drift early.

Buying Guide

Before purchasing the 1771-ILK, verify compatibility with your PLC-5 chassis and backplane capacity. The module uses a 1771-WF wiring arm (sold separately). For current lifecycle status and availability, contact BluePLC Industrial. Our team can help you confirm the 1771-ILK meets your application requirements and suggest alternatives if needed.