GE UR Series Modules: UR6AV Digital I/O Module —

Technical Dossier

Product Details And Specifications

GE UR Series: Comprehensive Module Range and Technical Overview

The GE Grid Solutions UR Series (Universal Relay) platform is one of the most widely deployed protection relay architectures in global heavy industry. Installed across high-voltage substations, chemical processing plants, nuclear generating stations, and petroleum refinery switchgear, the UR platform provides modular, slot-based protection, control, and monitoring for transmission and distribution systems rated from 5 kV to 765 kV. Its chassis-based architecture allows utilities and industrial operators to configure relay functionality precisely to application requirements, making it the reference standard for IEC 61850-compliant protection systems in North America, Europe, and Asia-Pacific.

The UR6AV is a Digital I/O module within the UR platform, providing configurable contact inputs and output relays for integration with external switching, tripping, and alarm circuits. It occupies a standard UR module slot and communicates over the UR backplane bus, making it directly interchangeable within any compatible UR chassis without firmware reconfiguration of the host relay.

The Evolution of UR Series Architecture

The UR platform was introduced by GE Multilin in the late 1990s as a successor to discrete electromechanical and first-generation numerical relay designs. The architecture is built around a 19-inch rack-compatible chassis accepting up to 12 plug-in modules across CPU, I/O, power supply, and communications slots. Early UR deployments used RS-485 serial communications (DNP3, Modbus RTU); subsequent generations added IEC 61850 GOOSE messaging over Ethernet, IEEE 1588 precision time protocol synchronization, and IEC 61968/61970 CIM-compatible data models.

The platform has remained backward-compatible across hardware generations, meaning UR6AV and equivalent I/O modules produced in different manufacturing runs retain pin-compatible backplane interfaces. However, firmware compatibility between module generations must be verified against the host relay's firmware revision table before substitution. Modules manufactured prior to 2005 may require firmware downgrade or chassis-level compatibility assessment when used as replacements in post-2010 installations.

As of 2024, the UR Series is in a mature/sustained phase. GE Vernova (successor to GE Grid Solutions) continues to supply spare modules and provide firmware support, but new relay designs are migrating toward the UR-series successor platforms. For installations with long operational horizons (10–25 years), lifecycle extension planning — including spare module stockpiling and third-party MRO sourcing — is a standard practice among asset managers.

UR Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly deployed modules within the GE UR Series platform. Modules are classified by functional category.

CPU / Main Processing Modules

UR6PP: Dual-redundant CPU module with integrated Ethernet port for UR platform relay processing.
UR6PH: High-speed CPU module supporting IEC 61850 Edition 2 and IEEE 1588 PTP synchronization.
UR6PC: Standard CPU module for legacy UR chassis; DNP3 and Modbus RTU native support.

Digital I/O Modules

UR6AV: 24-channel configurable digital I/O module; contact inputs and output relays for tripping and alarm circuits.
UR6AW: Extended digital output module; 16 Form-A output relays rated for high-current trip coil applications.
UR6AX: Digital input expansion module; 32 optically isolated contact inputs, 24 VDC/125 VDC selectable.
UR6AY: Mixed I/O module; 16 contact inputs and 8 output relays in single slot configuration.
UR6AZ: High-density digital I/O module; 48 contact inputs with configurable debounce timing.

Analog I/O Modules

UR6CT: Current transformer input module; 8-channel, 1A/5A selectable, for differential and overcurrent protection.
UR6VT: Voltage transformer input module; 4-channel, 69V/120V nominal, for voltage and frequency protection elements.
UR6AT: Analog transducer input module; 4–20 mA and 0–10 V inputs for RTD and process variable monitoring.

Communications Modules

UR6ET: Dual-port 100BASE-FX fiber Ethernet module for IEC 61850 GOOSE and MMS communications.
UR6EW: IEEE C37.94 teleprotection interface module for direct transfer trip over multiplexed fiber.
UR6RS: RS-485 serial communications module; DNP3, Modbus RTU, IEC 60870-5-103 protocol support.

Power Supply Modules

UR6DC: 125/250 VDC station battery power supply module; redundant input capability.
UR6AC: 120/240 VAC power supply module for installations without DC station battery.

Sourcing Hard-to-Find & Obsolete UR Series Parts

DriveKNMS maintains a dedicated inventory of GE UR Series modules, including production-discontinued variants no longer available through OEM distribution channels. For asset managers operating UR-based protection systems with 10+ year remaining service life, DriveKNMS provides lifecycle extension support through the following services:

Verified surplus stock of discontinued UR module variants, including pre-2010 CPU and I/O modules. Cross-reference matching between obsolete part numbers and current-production equivalents. Firmware version documentation to confirm compatibility between replacement modules and installed chassis. Emergency sourcing for critical spare requirements with expedited logistics to minimize substation downtime. All modules are supplied with traceable documentation of origin and, where applicable, OEM calibration records.

Quality Control for the UR Series Range

UR Series modules incorporate a proprietary backplane bus architecture that requires functional validation beyond standard power-on testing. DriveKNMS applies the following test protocol to all UR Series modules prior to shipment:

Backplane bus communication verification using a UR chassis test fixture to confirm module enumeration and data exchange with a reference CPU module. Digital I/O functional test: each contact input channel is exercised across its rated voltage range (24 VDC, 48 VDC, 125 VDC, 250 VDC as applicable); each output relay is actuated and contact resistance measured against OEM specification (<100 mΩ). Analog input calibration check: CT and VT input modules are verified against traceable reference signals at 0%, 50%, and 100% of rated input. Insulation resistance test: 500 VDC megger applied between I/O terminals and chassis ground per IEC 60255-27. Thermal soak: modules operated at 55°C for 4 hours to screen latent component failures. Firmware version audit: CPU modules are read for installed firmware revision and documented against the shipment record.

Modules that fail any test stage are quarantined and not offered for sale. Test records are available upon request for critical infrastructure procurement.