Allen-Bradley 1492-IFM40F-F24AD-4 Fusible Digital Interface Module

The Allen-Bradley 1492-IFM40F-F24AD-4, also cataloged as the 1492-IFM40F Fusible Digital Interface Module, operates as a dedicated hardware component for fused digital signal distribution and field circuit protection within ControlLogix I/O wiring systems. The module provides 40 interface points, 16 individually fused circuits, low-leakage blown fuse indication, and four isolated field groups.

Suffix Breakdown & Model Matrix

The supplied documentation identifies a fixed catalog configuration: 1492-IFM40F-F24AD-4.

Documented characteristics include:

• 40-point fusible interface

• 16 individually fused points

• 24 V AC/DC blown fuse indication

• 4 isolated groups

• 4 input terminals per group

• 40-pin cable interface

No official suffix decomposition is provided in the source data.

Hardware Specifications

I/O Density Scaling Characteristics

The 1492-IFM40F-F24AD-4 increases field termination density by consolidating 40 digital interface points into a single DIN-rail-mounted assembly. Four isolated groups permit segmentation of field circuits while maintaining a common interface structure to PLC I/O modules. The architecture supports migration from PLC-5 and Modicon 800 wiring schemes to ControlLogix platforms using prewired connection systems. Individually fused channels provide localized circuit protection without increasing terminal count.

Frequently Asked Questions

Q: Does the module provide fuse protection on all 40 interface points?
A: No. The module contains 16 individually fused points. The remaining interface connections operate according to the documented wiring configuration.

Q: Are the fuse elements supplied with the module?
A: No. The module utilizes 5 x 20 mm fuse clips, but fuse elements must be installed separately.

Q: Can the module be removed or rewired while energized?
A: The documentation does not specify hot-swap capability. Standard industrial practice is to de-energize associated circuits before replacing wiring, connectors, or fuse elements.

Field Installation Guidelines

• Mount the module on a properly secured DIN rail within the control enclosure.

• Verify that field wiring remains within the specified 12-22 AWG conductor range.

• Separate low-voltage signal conductors from higher-energy power wiring to reduce electrical interference.

• Confirm fuse ratings match the protected field circuit requirements before energization.

• Maintain clear identification of the four isolated groups during termination and commissioning.

• Inspect all 40-pin cable connections for proper seating before applying power.

• Replace blown fuses only with correctly rated 5 x 20 mm fuse types approved for the application.