Description

The Allen-Bradley 1746-NI16I is a high-density analog input module designed for the SLC 500 programmable logic controller (PLC) system. This module provides 16 single-ended, backplane-isolated input channels with 16-bit resolution, making it suitable for high-precision monitoring of current-based process signals. It is engineered to support a variety of current ranges, including 0 to 20 mA, 4 to 20 mA, and +/- 20 mA, facilitating integration into diverse industrial control environments.

Features

• 16-channel analog current input module for SLC 500 systems.
• 16-bit resolution for high-accuracy signal conversion.
• Supports multiple input signal types: 0-20 mA, 4-20 mA, +/- 20 mA, and 0-1 mA.
• Integrated open-circuit detection for rapid identification of sensor or wiring faults.
• Individual channel-to-channel isolation for enhanced noise immunity and signal integrity.
• Compact single-slot module design for efficient chassis space utilization.
• 25-pin D-shell connector interface for reliable field wiring.

Applications

• Oilfield water injection automation systems (pressure monitoring).
• Wastewater treatment plants (aeration tank DO and pH monitoring).
• Power station auxiliary control (transformer and bearing temperature monitoring).
• Hydraulic system monitoring for large-scale presses and rolling machines.

Technical Specifications

Installation Guidelines

• Ensure the PLC chassis is powered down before inserting or removing the module to prevent electrical damage.
• The module is designed for standard SLC 500 chassis mounting; ensure it is fully seated and the retaining screws are tightened.
• Use shielded twisted-pair cabling for analog signals to minimize EMI/RFI interference.
• Maintain proper grounding practices for the analog common terminal to ensure signal stability.
• Keep the module clear of high-voltage power lines and high-EMI sources within the control cabinet.
• If removing the terminal block, use the provided labeling to ensure correct re-wiring of input channels.

FAQs

What is the 1746-NI16I?

The Allen-Bradley 1746-NI16I is a 16-channel, high-resolution analog current input module designed for the SLC 500 platform.

How do I configure the 1746-NI16I module?

Configuration is performed in RSLogix 500 (offline or online) via the I/O configuration screen. It is a multi-class module, with Class 3 recommended for optimal performance.

What are the 1746-NI16I power requirements?

The module draws 125 mA at 5V DC and 75 mA at 24V DC from the SLC 500 backplane.

How can I detect a sensor disconnection?

The 1746-NI16I features built-in open-circuit detection, which allows the controller to report a fault condition if a sensor loop is broken.