DEChub 90 Ethernet Backplane Owner's Manual

This document is the Owners Manual for the DEChub 90 Ethernet Backplane, published by Digital Equipment Corporation in February 1991.

The manual serves as a comprehensive guide for the configuration, installation, and troubleshooting of the DEChub 90 Ethernet Backplane, along with the optional DEHUX wall mount plate and cover.

Key aspects covered include:

• Introduction: Provides an overview of the DEChub 90 backplane, describing it as an 8-slot hub for Digital's Work Group family of products. It facilitates ThinWire Ethernet connections, offers hot-swap capabilities, and includes a single auto-selecting power supply. The DEHUX wall mount plate and cover are introduced as accessories for flexible mounting (rack, solid wall, hollow wall, office partition) and component protection.
• Configuration: Details crucial rules and guidelines for setting up the DEChub 90 within various Ethernet network environments. This includes general network rules (e.g., segment lengths, repeater/bridge limits) and specific DEChub 90 rules regarding termination, placement within ThinWire segments (must be at an end), and the placement of DECbridge 90 Work Group Bridges (only one per backplane/work group, in specific slots 7 or 8). It also illustrates typical network configurations and common configuration errors.
• Installation and Troubleshooting: Provides step-by-step instructions for installing the DEChub 90 backplane in a 19-inch equipment rack or directly on a solid wall. It also covers installation using the DEHUX wall mount plate on various surfaces, including the installation of patch panels and the protective cover. A troubleshooting section helps users diagnose and resolve common issues, particularly related to the power supply and correct unit placement.
• Specifications and Parts List: Includes detailed physical dimensions, mechanical and electrical specifications (e.g., input voltage, power consumption, operating temperature), and a comprehensive list of parts included with both the DEChub 90 Backplane and the DEHUX Wall Mount and Cover.
• Related Documentation: Lists other relevant Digital Equipment Corporation manuals for network wiring and DECconnect systems.

The manual emphasizes that the DEChub 90 backplane, when populated with Work Group units, forms a work group hub that integrates into a structured wiring environment, aligning with industry standards like EIA/TIA-568.