Configured for serial communication expansion and offloaded process routines in 1771 I/O chassis, the Allen-Bradley 1771-DXPS (1771-DXPS/A Control Coprocessor) provides direct physical/electrical execution across PLC-5 backplane architectures.

Revision Designation & Variant Array

• Base Model: 1771-DXPS
• Spare Model Code: 1771-DXPS/A
• Hardware Series: Series A
• Functional Role: Serial expander module and dedicated control coprocessor for local ASCII or custom protocol handling.

Physical & Electrical Data

Backplane Integration & Data Exchange

The 1771-DXPS leverages high-speed backplane bus communication velocity to exchange data blocks directly with the host PLC-5 processor without degrading execution cycles. Built-in firmware flash compatibility allows deterministic handshaking over serial links, expanding ASCII peripheral connections while maintaining low-latency backplane throughput.

Package Delivery Contents

• 1 x 1771-DXPS Control Coprocessor Module
• 2 x Plastic Keying Bands
• 1 x Printed Installation Reference Guide

Cabinet Assembly & Mounting Protocol

• System Depressurization: Disconnect 1771 chassis power supplies and field voltage sources prior to module seating.
• Physical Keying Setup: Position plastic keying bands on the backplane connector between pins 10/12 and 18/20 to prevent improper slot insertion.
• Chassis Insertion: Slide the module firmly into the designated 1771 I/O slot until the top and bottom latching mechanisms lock securely.

Frequently Asked Questions

• Q: What is the primary function of the 1771-DXPS module?

  It serves as a serial expander coprocessor to offload custom serial routines and ASCII data processing from the main PLC-5 processor.

• Q: Can the 1771-DXPS be inserted while the chassis power is active?

  No, inserting or removing the module under power causes electrical arcing and can damage backplane bus traces.

• Q: What is the exact weight of the shipping package?

  The physical shipping weight of the 1771-DXPS module is 0.9 kg (1 lbs).

• Q: Where are the keying bands placed on the backplane for this unit?

  Keying bands are fitted on the backplane connector upper and lower pin sets according to standard 1771 slot keying guidelines.

• Q: Does the 1771-DXPS require a dedicated slot in the 1771 rack?

  It installs into any available standard 1771 I/O rack slot except the far-left slot reserved for the main processor or adapter.

• Q: How does the module transfer data to the local PLC-5 controller?

  Data exchange occurs across the 1771 backplane bus using block transfer read and block transfer write instructions.

• Q: What hardware revision corresponds to the spare code 1771-DXPS/A?

  The spare model code 1771-DXPS/A denotes Series A hardware production units.

• Q: What are the outer dimensions for freight shipping?

  Estimated package dimensions measure 3.2 cm x 27.3 cm x 15.2 cm.