The General Electric UR7HH is a high-performance inter-relay communications module designed for the Universal Relay (UR) series. This horizontal unit facilitates robust data exchange between protection relays, utilizing multi-mode fiber optic technology to ensure reliable communication in demanding industrial environments.

Features

• Two independent, full-duplex communication channels.
• 820 nm multi-mode fiber optic interface for long-distance, noise-immune connectivity.
• Standard ST-type fiber optic connectors for secure physical termination.
• Optical galvanic isolation rated at 2 kV to protect internal circuitry from ground loops and electrical surges.
• Wide operating temperature range suitable for harsh substation environments.

Technical Specifications

Installation Guidelines

• Ensure the UR relay is powered down before inserting or removing the UR7HH module from the back-plane.
• Handle the module by the edges to avoid electrostatic discharge (ESD) damage to sensitive internal components.
• Ensure fiber optic cables are routed with appropriate bend radii to prevent signal attenuation or fiber breakage.
• Verify that ST connectors are clean and properly seated before locking them into the module ports.
• The module is designed for horizontal mounting within the UR chassis; ensure the mounting screws are tightened to maintain proper grounding and structural integrity.

FAQ

What type of fiber optic cable is compatible with the UR7HH?

The module is designed for 62.5/125 µm multi-mode fiber optic cables using standard ST connectors.

Does this module require external power?

No, the UR7HH draws its required +5 V DC power directly from the Universal Relay back-plane.

What is the primary application for this module?

This module is primarily used for inter-relay communication, allowing protection relays to share data for schemes such as differential protection or interlocking in power distribution systems.