Product Overview

The Allen-Bradley 1746-IG16​ is a high-density, 16-channel digital input module designed for the Allen-Bradley SLC 500 modular programmable logic controller (PLC) system. This module serves as a critical interface between the PLC’s central processor and the field devices, providing a reliable means to read the on/off status of sensors, switches, pushbuttons, and other discrete devices. Specifically configured for 24VDC sinking (NPN) input circuits, the Allen-Bradley 1746-IG16​ is engineered to convert the presence or absence of a 24VDC signal at its terminals into a logical 1 or 0 that the SLC 500 processor can utilize in its control program. Each of its 16 channels is individually isolated in groups and features diagnostics like LED status indicators, making it a fundamental component for machine control, process monitoring, and safety interlocking in a wide range of industrial automation applications.Installed into any available I/O slot of an SLC 500 chassis (such as the 1746-A7), the 1746-IG16​ module communicates with the processor via the chassis’s high-speed parallel backplane. Its design emphasizes ease of use and reliable signal acquisition in noisy industrial environments. The module’s input circuits require a 24VDC sourcing (positive) common, meaning the field device (sensor/switch) acts as the sink to ground when activated. This is a common configuration for many industrial proximity sensors and photoelectric switches. The Allen-Bradley 1746-IG16​ provides internal optical isolation between the field wiring and the controller’s logic, protecting the sensitive processor from voltage transients and ground loops that can occur in plant environments. With its balanced 16-point density, it offers an efficient use of chassis space, allowing a significant number of digital sensors to be monitored from a single module slot. As a core part of the extensive SLC 500 I/O family, the 1746-IG16​ represents a proven, cost-effective solution for gathering discrete status information in centralized control systems, contributing to the platform’s reputation for durability and straightforward integration.

Technical Specifications