Allen Bradley 2085-ECR Micro800 Expansion Bus Terminator End Cap

Product Overview

The Allen Bradley 2085-ECR serves as the mandatory bus terminator for the Micro800 expansion I/O system. This end cap secures the right-hand side of the final expansion module in a Micro850 or Micro870 controller assembly. It completes the serial communication backplane circuit, ensuring signal integrity across all connected I/O modules. Without the 2085-ECR, the controller cannot establish a stable communication link with the expansion rack, leading to bus errors and system downtime. It functions as both an electrical terminator and a physical protective cover for the open bus interface.

Technical Specifications

Engineering Advantages

• Signal Integrity Optimization: The 2085-ECR eliminates signal reflections on the high-speed serial bus. By providing the correct impedance matching at the end of the line, it prevents data corruption and ensures synchronized I/O updates between the processor and expansion modules.

• Hazardous Environment Compliance: This terminator carries full certification for Class I, Division 2 (Groups A, B, C, and D) hazardous locations. This allows engineers to deploy Micro800 systems in oil and gas applications or chemical processing zones where explosive gases might exist.

• Rugged Physical Protection: Beyond its electrical function, the 2085-ECR protects the delicate backplane pins from dust, moisture, and accidental contact. The IP20-rated enclosure prevents debris from shorting out the 5V DC logic power distributed across the expansion bus.

• Wide Thermal Envelope: Reliable operation from -20°C to 65°C supports installation in unheated outdoor enclosures or high-temperature engine rooms. The unit maintains electrical termination constants regardless of thermal fluctuations.

• Simplified Hardware Integration: The "End Cap" design allows for tool-free installation. It snaps directly onto the last module in the rack, completing the mechanical and electrical assembly of the PLC system in seconds.

FAQs

• Is the 2085-ECR supplied as 100% Brand New?

  Yes. We supply this 2085-ECR bus terminator in 100% Brand New, original factory condition. Every unit ships in original Allen Bradley packaging to ensure the pins and housing remain pristine for your installation.

• Can the system operate without the 2085-ECR installed?

  No. The Micro850 and Micro870 controllers require the 2085-ECR to detect the end of the expansion rack. If the terminator is missing, the controller will typically report a "Bus Fault" and fail to recognize any attached 2085 expansion I/O modules.

• Does this terminator require any software configuration?

  The 2085-ECR is a passive electrical component. You do not need to configure it in Connected Components Workbench (CCW) software; however, the software assumes a properly terminated bus for the I/O configuration to validate.

• Where exactly should I install the 2085-ECR?

  Always install the 2085-ECR on the right side of the very last expansion I/O module in your hardware stack. If you are not using any expansion modules, the terminator is not required, as the controller’s base unit handles its own internal termination.