OVERVIEW

Official designation: Allen-Bradley 1746-IV16 (SLC 500, Sourcing Discrete Input Module)

The 1746-IV16 is a 16-point Sourcing (current-sinking) DC digital input module for the SLC 500 system, operating on a 24V DC nominal voltage (10 to 30V DC range).

KEY SPECS SUMMARY

Power: 5V DC, 85 mA (backplane)

Interfaces / Ports: One 36-pin connector

Indicators: Sixteen Input Status LEDs

Operating Temp: 0 to 60 degrees C

Platform / Compatibility: SLC 500 modular hardware

Limit: 16 individual channels

Lifecycle: Active replacement part

FREQUENTLY ASKED QUESTIONS

Technical Specifications:

Q: What is the required current draw from the 5V DC SLC 500 backplane for this module?

A: The module draws 85 mA from the 5V DC backplane power supply.

Wiring & Installation:

Q: In a sourcing module, what determines the input status from an external field device?

A: Sourcing inputs require the external device to sink current from the module's input terminals.

Troubleshooting & Compatibility:

Q: What action should be taken if an input status LED is not illuminating despite a connected sensor?

A: Verify that the 24V DC field power is correctly supplied and that the external sensor is properly sinking current.

Replacement & Upgrades:

Q: What is the recommended upgrade path when modernizing from the 1746-IV16 to newer platforms?

A: Migration typically involves using ControlLogix or CompactLogix 24V DC Sinking/Sourcing input modules.