Product Overview

The Allen-Bradley 1734-EP24DC​ is a 24V DC Power/Bus Extension Module in the Bulletin 1734 POINT I/O family — Rockwell Automation’s modular, rackless distributed I/O system. It is important to be precise about what this module is and is not: it is not a standalone AC-to-DC power supply, and it is not a module that creates a new independent power segment. The Allen-Bradley 1734-EP24DC​ is an extension module that passes the incoming 24V DC field power straight through to the modules on its right while injecting additional POINTBus backplane current, extending the number of I/O modules a single POINT I/O adapter can support. Rockwell lists the product as Active, so it remains a current catalog item rather than a legacy spare.Physically, the Allen-Bradley 1734-EP24DC​ occupies a single POINT I/O slot width and snaps onto a standard 35 mm DIN rail using the same interlocking side pieces as every other 1734 module, with the removable terminal block (RTB) on top carrying the 24V DC input. Its dark grey housing provides immediate visual identification in a mixed I/O bank. The module is invisible to the controller: it does not appear as a node in the Studio 5000 / RSLogix 5000 I/O tree, and it consumes no input or output data — it simply passes field power and reinforces bus power.The module’s value is concentrated in two capabilities. First, it lets an I/O bank grow beyond the current budget of the adapter: depending on the current draw of the individual modules, a system can expand in 4-to-17-module increments, all the way to the architecture maximum of 63 I/O modules. Second, by placing the Allen-Bradley 1734-EP24DC​ between groups of modules, the designer creates a new field-voltage partition — meaning a fault, short or power interruption on one side cannot drag the entire bank down. This functional partitioning is what turns a large, vulnerable I/O string into a fault-tolerant architecture.

Technical Specifications