PRODUCT DETAILS
1794-AENT — FLEX I/O EtherNet/IP Adapter Module
The 1794-AENT is the EtherNet/IP adapter module for the 1794 FLEX I/O system. It connects a FLEX I/O node to an EtherNet/IP network, presenting up to eight I/O modules installed in the same node to the controller as a remote I/O device. The controller reads and writes I/O data over the network as if those modules were in the local chassis. Each FLEX I/O node requires one adapter — the 1794-AENT is the adapter for EtherNet/IP-based systems.
Specifications
| Parameter | Value |
|---|---|
| Part Number | 1794-AENT |
| Platform | FLEX I/O (1794) |
| Network Protocol | EtherNet/IP (CIP) |
| Ethernet Speed | 10/100 Mbps, auto-negotiate |
| Ethernet Ports | 1 × RJ-45 |
| Max I/O Modules per Node | 8 |
| I/O Messaging | Class 1 cyclic (I/O) and Class 3 / UCMM (explicit) |
| IP Address Assignment | BOOTP, DHCP, or static (via rotary switches or software) |
| Field Power Pass-Through | Yes — V+ and V− rail to downstream terminal bases |
| Backplane Current (5V) | 600 mA available to I/O modules |
| Control Power | 24V DC (from field power rail) |
| Operating Temperature | 0°C to 55°C |
| Standards | EtherNet/IP conformance tested, UL 508, CE |
FLEX I/O Node Architecture
A FLEX I/O node is a chain of terminal bases on a DIN rail. The adapter module clips into the first terminal base at the left end; up to eight I/O modules clip into the remaining bases to the right. The adapter communicates with the controller over EtherNet/IP and exchanges I/O data with the attached modules over the FLEX I/O backplane rail built into the terminal base chain.
The field power rail (24V DC) enters the node at the adapter's terminal base and passes through to all subsequent terminal bases — field power for all eight modules comes from the same entry point. If a new power segment is needed partway through the node, a 1794-TB3S terminal base with separate power rails or a power extender module can split the node into independently-powered segments.
FAQ
Q: Does the 1794-AENT support Device Level Ring (DLR) topology?
No. The 1794-AENT has a single Ethernet port and does not support DLR. For DLR capability on FLEX I/O, the 1794-AENTR (dual-port) adapter is required.
Q: How many 1794-AENT nodes can one controller manage?
The limit is the controller's EtherNet/IP connection count and backplane current budget — not a fixed node count. Each node consumes one EtherNet/IP connection. Controllers with 256+ connections support dozens of FLEX I/O nodes simultaneously.
Q: What happens to I/O if the EtherNet/IP connection is lost?
The adapter executes the configured connection loss action for each I/O module — typically outputs de-energize (go to 0) and inputs hold last state until reconnection. The specific fault behavior per module is configurable in Studio 5000.
Q: Can analog and digital modules be mixed in the same node?
Yes. The eight module slots accommodate any combination of FLEX I/O module types — digital, analog, specialty (thermocouple, RTD, counter) — in any order. The adapter presents all of them over the single EtherNet/IP connection.

