Allen-Bradley 1746-NI04V/A Analog Input Module

The Allen-Bradley 1746-NI04V/A, also cataloged as the 1746-NI04V/A analog input module, serves as the primary 1746-NI04V/A voltage input module utilized to execute ±10 V DC signal acquisition across SLC 500 backplane I/O scan architectures. The module converts four-channel analog voltage signals into 14-bit digital values through synchronized end-of-scan updates within the SLC 500 processor cycle.

Suffix Breakdown & Model Matrix

No functional suffix segmentation is defined for 1746-NI04V/A. The designation represents a fixed 4-channel voltage input configuration within the SLC 500 NI04 analog input family.

Hardware Specifications

SLC 500 Backplane Voltage Acquisition Architecture

The 1746-NI04V/A performs voltage-to-digital conversion through internal sampling synchronized to the SLC 500 backplane scan cycle. Each channel is multiplexed into a shared conversion pipeline, with filtered input conditioning applied prior to quantization.

Backplane data transfer occurs via fixed memory mapping into processor input image tables. End-of-scan update behavior ensures deterministic alignment between controller scan execution and analog acquisition states. Input filtering stages reduce high-frequency noise coupling prior to A/D conversion, improving stability of ±10 V DC measurement channels.

Frequently Asked Questions (FAQ)

Q: Can the 1746-NI04V/A be hot-swapped during operation?
A: No. Module insertion and removal require chassis power shutdown due to SLC 500 backplane electrical architecture.

Q: What is the backplane load requirement of this module?
A: The module consumes approximately 120 mA at 5 V DC from the SLC 500 backplane and must be included in rack power budgeting.

Q: Does each channel support independent scaling?
A: Yes. Each of the 4 input channels is independently mapped to ±10 V DC measurement range with 14-bit resolution.

Field Installation Guidelines

Install the module in a single-slot SLC 500 chassis position with verified backplane capacity. Ensure all voltage input wiring uses shielded twisted pair conductors with correct polarity identification. Maintain separation between analog signal wiring and high-voltage conductors to reduce electromagnetic coupling. Ground cable shields at a single panel reference point only. Verify terminal block seating integrity before energizing the system to prevent intermittent measurement drift.