Description

GE Multilin UR7DH UR-7DH Inter-Relay Communications Module

The GE Multilin UR7DH, also cataloged as the UR7DH Inter-Relay Communications Module, operates as a dedicated hardware component for high-speed optical data exchange between GE Multilin Universal Relay devices using direct fiber communication links.

Hardware Specifications

Parameter	Specification
Model	GE Multilin UR7DH
Brand	General Electric Multilin (GE)
Module Type	Inter-Relay Communications Module (COMMS 7D)
Origin	Markham, Ontario, Canada
Weight	1.2 kg
Dimensions	6 in L x 7 in W x 1.5 in H
Operating Temp	-40 deg C to +70 deg C
Power Consumption	Module power supplied through UR chassis backplane
Platform Compatibility	GE Multilin Universal Relay (UR) Series
Communication Interface	Direct fiber serial link
Optical Source	1300 nm single-mode laser
Channel Count	1 channel
Fiber Type	Single-mode fiber (SMF)
Communication Protocol	GE Multilin Direct High-Speed Inter-Relay Protocol
Form Factor	UR chassis slot insertable module

Profinet / EtherNet-IP Deterministic Networks and Backplane Integration

The UR7DH module integrates with the GE Multilin Universal Relay architecture through the UR chassis backplane interface. The module provides deterministic peer-to-peer communication without external protocol converters, supporting protection schemes requiring direct relay-to-relay signal exchange.

The optical interface uses a 1300 nm single-mode laser transmitter for low attenuation fiber links. The fiber serial connection provides electromagnetic interference resistance and maintains signal integrity in substation environments.

Frequently Asked Questions

Q: What communication medium is supported by the GE Multilin UR7DH?
A: The module uses single-mode fiber (SMF) with a 1300 nm optical laser interface for direct high-speed inter-relay communication.

Q: Can the UR7DH operate as a standalone communication device?
A: No. The UR7DH is designed as a UR chassis slot insertable module and requires installation within a compatible GE Multilin Universal Relay platform.

Q: What protection applications use the UR7DH communication link?
A: The module supports relay communication schemes including line current differential protection, direct transfer tripping (DTT), permissive overreaching transfer trip (POTT), and inter-relay interlocking.

Field Installation Guidelines

• Install the UR7DH module only in a compatible GE Multilin Universal Relay chassis slot.
• Verify chassis power removal before module insertion or removal to prevent electrical damage.
• Route fiber optic cables separately from high-voltage conductors and high-current wiring to reduce mechanical stress and accidental fiber damage.
• Maintain proper fiber bend radius according to the installed cable specification.
• Use appropriate fiber cleaning procedures before connecting optical interfaces.
• Bond and ground the relay enclosure according to substation protection panel grounding practices.
• Confirm communication link status after installation using relay configuration and diagnostic functions.

Specifications

• Brand: General Electric

Advantages

• High reliability in industrial environments
• Supports continuous operation
• Compatible with major PLC/DCS systems