Description
RELIANCE 57C404C is a network communications module for Reliance Electric AutoMax PLC systems. It plugs into the AutoMax rack backplane and converts internal PLC data into a serial network format so multiple controllers and remote I/O can share data over a common network.
Product description and parameters
The 57C404C is a printed circuit assembly designed specifically for AutoMax / DCS networked systems. In a typical installation, it provides a dedicated network interface for one AutoMax processor module, supporting deterministic communication between racks.
RELIANCE 57C404C
Typical parameters for this class of module include:
- Power requirements
- Backplane supply (no separate field power terminals).
- Internal consumption in the low‑watt range suitable for AutoMax racks.
- Electrical interface
- One or more serial network ports on the front panel (e.g. shielded connector for the AutoMax or DCS network cable).
- Isolated transceivers to protect the PLC from line disturbances.
- Functional characteristics
- Supports AutoMax / DCS network protocol at fixed baud rates.
- Handles message routing between CPUs, I/O racks, and operator interfaces.
- Provides error detection and retry mechanisms on the network.
- Mechanical
- Form factor: AutoMax rack plug‑in module.
- Edge connector at the rear for backplane connection.
- Front panel with status LEDs (network active, error, module OK) and the network connector.
- Environmental
- Designed for standard control‑cabinet environments (typical industrial temperature and humidity ranges).
As a “C” revision of 57C404, 57C404C is a later hardware revision intended to be functionally compatible with earlier versions while incorporating minor hardware updates or improvements.
Datasheet‑style overview
A datasheet for 57C404C normally includes:
- Nominal backplane voltage and current draw.
- Network connector type and wiring (shield, signal lines, termination).
- Supported network speeds and maximum node count.
- LED functions for status and diagnostics.
- Mechanical outline (board height, depth, front‑panel layout).
- Operating and storage temperature ranges.
The module’s role is to offload communication handling from the CPU and provide a robust interface to the AutoMax/DCS network.
Origin
57C404C was designed and manufactured under the Reliance Electric brand (later associated with Rockwell/other corporate transitions). It is an industrial‑grade module originally sold into North American and global markets as part of Reliance Electric’s PLC and drive‑control ecosystem.
Recommended related Reliance Electric models
If you are working with 57C404C in an AutoMax environment, other commonly used Reliance Electric modules from the same brand include:
- 57C404 (earlier revisions)
Earlier revision of the same network communications module. Useful as a reference or replacement when exact revision is not critical. - AutoMax processor modules (e.g. 57C4xx CPU modules)
Main CPU/processor cards that execute ladder or structured control logic, using 57C404C to exchange data with other racks and HMIs. - AutoMax I/O modules (digital and analog)
Various 57C‑series I/O cards (digital input, digital output, analog input, analog output) that connect field devices to the AutoMax backplane controlled over the network. - Other communication modules in the series
Modules for different networks or protocols within the same AutoMax family, used when integrating with external systems or legacy networks beyond the standard AutoMax/DCS bus.
These related modules, together with 57C404C, form a complete distributed control system where the network communications module is the key link between distributed racks and central or peer controllers.
