TC-MUX021 | 51404391-125 | Serial Communication Interface Module | Honeywell

Product Description

The TC-MUX021 (51404391-125) is a high-performance serial multiplexer interface designed for integration within Honeywell Experion PKS and legacy PLC architectures. This module acts as a specialized communication bridge, enabling the controller backplane to interface with serial-based field devices and peripheral subsystems. Engineered for industrial reliability, it manages data flow across multiple serial channels, ensuring deterministic timing and data integrity for critical process variables.

Technical Specifications

• Model Identification: TC-MUX021

• Associated Part Number: 51404391-125

• Primary Function: Serial Multiplexing / Device Interface

• Operating Voltage: 24 VDC (Nominal)

• Current Consumption: 1.0 to 1.3 Amps

• Input Current: 5.6 mA (typical signal load)

• Form Factor: Rack-mounted PLC I/O slot

• Physical Mass: 0.48 kg (approx. 1.06 lbs)

• Lifecycle Status: Discontinued by Manufacturer (Legacy Spares Support)

Operational Utility and Integration

The TC-MUX021 (51404391-125) is frequently deployed in process industries where legacy serial sensors, barcode readers, or specialized flow meters must communicate with a modern DCS or PLC backplane. Its robust 24VDC design and high-current tolerance (up to 1.3A) reflect its capability to handle complex multiplexing tasks across multiple ports without signal degradation. As a discontinued component, it remains a vital inventory item for maintaining the communication infrastructure of existing Honeywell control rooms.

Frequently Asked Questions

• What specific serial protocols does this module support?

  The TC-MUX021 typically interfaces with standard RS-232, RS-422, or RS-485 signaling, depending on the software configuration and cable pinouts used at the terminal block.

• Can this module be hot-swapped in a powered rack?

  While many Honeywell I/O modules support live insertion, it is best practice to verify that the serial communication loop is paused or that the redundant controller is active before swapping the TC-MUX021 (51404391-125) to avoid transient data errors.