GE UR Series Modules: UR6FH Digital I/O Module —

Technical Dossier

Product Details And Specifications

GE UR Series: Comprehensive Module Range and Technical Overview

The GE UR (Universal Relay) Series, developed by GE Grid Solutions (formerly GE Multilin), is one of the most widely deployed protection relay platforms in global heavy industry. Installed across chemical processing plants, nuclear power stations, petroleum refineries, hydroelectric facilities, and high-voltage transmission substations, the UR platform provides a standardized, modular architecture for generator protection, transformer protection, line protection, bus protection, and motor protection applications. Its chassis-based, slot-configurable design allows end users to build application-specific relay configurations from a common hardware library, reducing spare parts inventory complexity across multi-unit installations. The UR Series is recognized under IEC 61850 GOOSE messaging standards and supports legacy SCADA integration via DNP3, Modbus RTU, and IEC 60870-5-104 protocols, making it a long-term fixture in both greenfield and brownfield substation environments.

The Evolution of UR Series Architecture

The UR platform was introduced in the late 1990s as a successor to GE's earlier SR (System Relay) and DFP (Digital Fault Protection) product lines. The first-generation UR chassis used a parallel backplane bus architecture with proprietary inter-module communication. Second-generation revisions introduced the UR IED (Intelligent Electronic Device) communication layer, enabling peer-to-peer GOOSE messaging and time-synchronized sampling via IEEE 1588 PTP. The third-generation UR firmware (version 7.x and above) added cybersecurity hardening aligned with NERC CIP standards, role-based access control, and encrypted communications. Hardware modules across generations maintain backward mechanical compatibility within the same chassis form factor, though firmware and communication card compatibility must be verified when mixing module generations. The UR Series has entered a mature lifecycle phase; GE Grid Solutions continues to supply replacement modules and firmware updates, but new platform development has shifted toward the UR-series successor platforms. For installations committed to the UR architecture, long-term maintenance sourcing from authorized distributors and certified aftermarket suppliers is the primary continuity strategy.

UR Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly deployed modules within the GE UR Series platform, organized by functional category:

Digital I/O Modules

• UR6FH: 24-channel digital I/O module; configurable contact inputs and output relays for protection logic interfacing.
• UR6GH: High-density digital output module; 16 Form-A output relays rated for high-current switching applications.
• UR6EH: Digital input module; 24 optically isolated contact inputs, 24 VDC/125 VDC wet/dry contact compatible.
• UR6DH: Mixed digital I/O module; 16 contact inputs and 8 Form-C output relays for general protection tripping circuits.

Analog I/O & Transducer Modules

• UR6AH: Analog input module; 4-channel, 4–20 mA / 0–10 V transducer input for RTD and thermocouple monitoring.
• UR6BH: CT/VT analog input module; 8 current transformer and 4 voltage transformer inputs for metering-class accuracy.
• UR6CH: High-accuracy analog module; 16-bit ADC resolution, used in differential protection and power quality applications.

CPU & Processing Modules

• UR9FH: Main CPU module; dual-core processor, 512 MB RAM, hosts UR firmware and IED logic engine.
• UR9GH: Redundant CPU module; hot-standby configuration for critical protection applications requiring no single point of failure.
• UR9EH: Legacy CPU module; single-core, compatible with UR firmware versions 4.x through 6.x.

Communication & Network Modules

• UR7FH: IEC 61850 communication module; dual Ethernet ports, GOOSE publisher/subscriber, MMS server.
• UR7GH: Multi-protocol communication module; DNP3, Modbus TCP/RTU, IEC 60870-5-104 simultaneous support.
• UR7EH: Fiber optic communication module; ST-connector, 820 nm multimode, for electrically noisy substation environments.
• UR7DH: IEEE 1588 PTP grandmaster-capable time synchronization module; IRIG-B and PPS output.

Power Supply Modules

• UR8FH: DC power supply module; 125/250 VDC input, 5 VDC / 12 VDC regulated output for chassis backplane.
• UR8GH: AC/DC universal power supply module; 85–264 VAC / 88–300 VDC wide-range input, redundant output capable.
• UR8EH: Redundant power supply module; hot-swap capable, used in N+1 power redundancy configurations.

Sourcing Hard-to-Find & Obsolete UR Series Parts

Quality Control for the UR Series Range

UR Series modules incorporate a high-density backplane bus with proprietary inter-slot communication protocols that require specialized test procedures beyond standard bench testing. DriveKNMS applies a multi-stage quality control process to all UR Series modules processed through its facility. Stage 1: Visual inspection of PCB, connector pins, and chassis mounting hardware against GE Grid Solutions mechanical drawings. Stage 2: Powered functional test using a UR chassis test fixture with active backplane communication, verifying module self-identification, firmware version reporting, and I/O channel continuity. Stage 3: For digital I/O modules including the UR6FH, each contact input channel is individually stimulated and verified against the module's channel map; each output relay is energized and contact resistance measured. Stage 4: Communication modules undergo protocol-level testing with live IEC 61850 and DNP3 traffic to confirm message integrity and timing compliance. Stage 5: Final burn-in at rated operating temperature for 24 hours prior to packaging. All test records are retained and available upon request with shipment documentation.