OVERVIEW

Official designation: Allen-Bradley 1746-NR4 (SLC 500, RTD/Resistance Analog Input Module)

The 1746-NR4 is a dedicated SLC 500 module providing four channels for high-accuracy resistance temperature detector (RTD) and direct resistance measurements in industrial control environments.

KEY SPECS SUMMARY

Power: 5V DC, 270 mA (backplane)

Interfaces / Ports: One 36-pin connector

Indicators: No external indicators

Operating Temp: 0 to 60 degrees C

Platform / Compatibility: SLC 500 modular hardware

Limit: Four isolated channels

Lifecycle: Discontinued

FREQUENTLY ASKED QUESTIONS

Technical Specifications:

Q: What are the primary types of sensors the 1746-NR4 module is capable of monitoring?

A: It monitors Platinum, Copper, and Nickel RTDs, plus direct resistance up to 500 ohms.

Wiring & Installation:

Q: What specific wiring configurations are supported by the RTD input channels?

A: The module supports 2-, 3-, and 4-wire RTD input configurations per channel.

Troubleshooting & Compatibility:

Q: What are common causes for a high resistance error when using the 1746-NR4 module?

A: Errors usually result from incorrect sensor wiring, open circuits, or exceeding the 500 ohm range limit.

Replacement & Upgrades:

Q: Is there a modern Rockwell Automation platform successor recommended for this SLC 500 module?

A: Current systems generally transition to CompactLogix or ControlLogix platforms for modern RTD control.