Allen-Bradley 8500-1746I SLC 500 Interface Module

The Allen-Bradley 8500-1746I, also cataloged as the 8500-1746I Adapter Module Interface, serves as the primary 1746 PLC Module/Rack utilized to execute internal I/O ring data routing and backplane power distribution across Allen-Bradley SLC 500 automation platforms. Operating directly on the rack backplane assembly, the unit conditions control logic signals and delivers isolated signal conversion between local processor buses and expansion I/O racks without requiring external active buffer cards.

Hardware Specifications

Backplane Bus Communication Velocity & I/O Density Scaling

The module operates directly via the native 1746 backplane architecture, maintaining high-speed parallel bus transmission rates and low latency cycle execution across expanded I/O chassis assemblies. Signal routing circuits handle deterministic I/O scan sequences while suppressing differential noise and EMI artifacts over the internal rack connector pins. Firmware handshake routines synchronize backplane data frames between the local processor and downstream expansion interface nodes, preserving backplane bus communication velocity and preventing buffer overrun errors during dense I/O scaling setups.

Frequently Asked Questions

Q: What is the primary backplane power consumption requirement for the 8500-1746I module?

A: The module draws a continuous current of 0.175 AMP strictly from the 5 VDC backplane bus supplied by the system chassis power supply.

Q: Can the 8500-1746I interface module be removed or inserted while the SLC 500 rack is powered up?

A: No. The 8500-1746I does not support RIUP (Removal and Insertion Under Power). System power to the 1746 chassis backplane must be completely shut off before module removal or installation to prevent hardware damage and processor faults.

Field Installation Guidelines

1. Verify that the system main circuit breaker and backplane power supply are completely de-energized before inserting or removing the module.
2. Align the circuit board card guides with the top and bottom rails of the targeted 1746 chassis slot.
3. Slide the module firmly into the slot until the top and bottom retention latches snap securely into place, ensuring complete seating of the backplane connector pins.
4. Maintain a minimum clearance of 50 mm (2 inches) above and below the chassis assembly to facilitate passive thermal dissipation.
5. Route incoming field wiring in separate conduits away from high-voltage AC power lines to prevent electromagnetic coupling onto low-voltage backplane communication traces.