Molex SST-ESR2-CPX-P | CompactLogix Modbus Module

Description

Product Overview

Communication gaps between a PLC and field equipment can complicate commissioning, especially when Ethernet-based controllers must exchange data with devices that still use serial Modbus. The Molex SST-ESR2-CPX-P addresses this requirement as an in-chassis communication module designed for Rockwell Automation CompactLogix controllers. It supports Ethernet Modbus TCP/UDP alongside serial Modbus RTU/ASCII, allowing a controller to exchange process data with compatible drives, meters, instruments, and other networked devices. Its primary purpose is protocol communication, not direct acquisition of conventional hardwired digital or analog signals.

The Plus version provides one 10/100 Mbps Ethernet port and two configurable serial ports supporting RS-232, RS-422, or RS-485 connections. It supports Modbus master and slave operation, with Ethernet client/server functions and up to 256 commands per port. A shared data area of up to 32,000 words supports the exchange of input, output, and status information with the PLC application. Configuration is handled through SST configuration software, and the module includes a microSD card for configuration storage and transfer. Direct process-data mapping into the Logix controller helps reduce the need for custom ladder logic dedicated solely to communication data handling.

For an existing CompactLogix installation, the Molex SST-ESR2-CPX-P can support integration of legacy serial equipment and Ethernet-based Modbus devices within one PLC architecture. Before selecting a replacement, verify the controller family, chassis compatibility, firmware and software support, serial wiring, and existing communication configuration. The Plus version should not be confused with the standard SST-ESR2-CPX-S, which has a different command-capacity specification. Published product references also indicate that the model has been discontinued, so condition, configuration retention, and functional-test evidence deserve particular attention during procurement. A successful replacement should be verified through actual Modbus exchanges, correct data mapping, and recovery behavior following communication interruptions.

Product Introduction (Non-Templated)

When a CompactLogix controller needs to communicate with both Ethernet and serial Modbus equipment, a dedicated communication module can simplify integration. The Molex SST-ESR2-CPX-P provides one 10/100 Mbps Ethernet port, two serial ports, and support for up to 256 commands per port.

For a legacy PLC upgrade, verify the controller platform, serial pinout, and stored configuration before installation. Since the model is discontinued, request a functional test covering both Ethernet and serial communication.

Key Technical Specifications

Specifications are based on the manufacturer’s SST ESR2-CPX product literature. Confirm the applicable hardware revision and controller compatibility before installation.

SST-ESR2-CPX-P

Related Products

The following products and accessories are relevant when maintaining or expanding an SST–P installation. They have different functions or configurations and should not automatically be treated as direct replacements.

1. SST–S — The standard version of the module. It provides Ethernet and serial Modbus communication but differs from the Plus version in command capacity. Confirm whether the existing application depends on the Plus model’s 256 commands per port.

2. 112073-0005 — The manufacturer engineering number for the SST–P Plus module. Use this identifier alongside the model number when checking labels, purchasing records, and configuration documentation.

3. 112073-0006 — The engineering number associated with SST–S. It identifies the standard variant rather than the Plus version, so compare command requirements before considering a substitution.

4. Rockwell Automation CompactLogix controllers — The intended controller ecosystem for the module. The exact controller model and supported chassis must be checked against the installation documentation before selecting a compatible communication module.

5. Rockwell Automation RSLogix 5000 / Logix engineering software — Used in the module’s configuration and controller integration workflow. Confirm software version compatibility and the availability of the required module profile or configuration files.

6. SST Configuration Console — The dedicated configuration utility used to configure communication behavior. Retain the existing configuration files and confirm that the required software version is available before replacing discontinued hardware.

7. microSD configuration card — Supports configuration storage and transfer for the module. Verify the card’s contents and configuration compatibility before using it to restore a replacement unit.

Frequently Asked Questions (FAQ)

1. What is x used for?

e connects a CompactLogix PLC to compatible Modbus devices over Ethernet and serial connections. Common applications include exchanging process values with instruments, reading drive status, transferring meter data, and integrating equipment that uses different Modbus interfaces.

It is a communication module rather than a conventional digital or analog I/O module.

2. What is the differencn and SST–S?

The main distinction is the Plus version’s higher command capacity.

• : Plus version, up to 256 commands per port.
• SST–S: Standard version with a different command-capacity specification.

Both versions support Ethernet and serial Modbus communication. Before changing variants, check the number of configured commands, communication workload, and existing project configuration.

s support RS-485 and Modbus RTU?

Yes. Its serial interfaces support RS-232, RS-422, and RS-485, with Modbus RTU and Modbus ASCII master/slave functionality. Serial operation can use baud rates from 110 bps to 115.2 kbps.

For commissioning, verify the serial wiring, device address, baud rate, parity, stop bits, and master/slave roles. A mismatch in any of these settings can prevent communication even when the hardware is functioning correctly.

4. Can e without rewriting my PLC logic?

Not necessarily. The module supports direct process-data mapping, which can reduce the amount of ladder logic required for communication handling. However, replacing the module does not guarantee that the existing project will work without changes.

Before removal:

1. Back up the controller project and module configuration.
2. Record the current data mapping and command list.
3. Preserve the microSD configuration where applicable.
4. Verify module recognition and communication after replacement.
5. Check that input, output, and status words retain their intended meanings.

s support firmware v3.1?

I cannot confirm firmware v3.1 compatibility for this exact module. The supported release depends on the module revision, CompactLogix controller, engineering software, and configuration utility.

Check the manufacturer’s compatibility documentation for the precise revision before updating firmware or changing controller software. Do not assume that a firmware version used by another SST communication module also applies to this model.

6. How can I verify a nes ?

A new-surplus description does not establish that the module has been tested or that its configuration is intact. Request:

• Photographs of the complete model number and manufacturer label.
• Confirmation of the Plus version and part number 112073-0005.
• Inspection results and functional-test records.
• Evidence that Ethernet and both serial ports operate correctly.
• Details of configuration-card contents, if included.
• Written warranty terms and return conditions.

For production applications, a test that confirms actual Modbus data exchange is more useful than a visual inspection alone.

7. What warranty and replacement support are available for this discontinued module?

Available parts references re as discontinued. Confirm the current manufacturer support position and whether software, configuration files, and technical documentation remain available.

Warranty coverage depends on the supplier and the unit’s condition. Obtain the warranty period, coverage for functional faults, return procedure, and any exclusions in writing. If the original module cannot be sourced, evaluate an alternative communication architecture against the existing PLC project, protocol requirements, and commissioning budget.

Procurement recommendation: Specify Molex /d , part number 112073-0005, and verify the Plus configuration before ordering. The critical checks are CompactLogix compatibility, the 256-command-per-port requirement, configuration retention, and successful Ethernet and serial Modbus testing.