GE Multilin UR Series Modules | UR6DV Digital I/O Input Universal Relay

Technical Dossier

Product Details And Specifications

GE Multilin UR Series: Comprehensive Module Range and Technical Overview

The GE Multilin UR (Universal Relay) platform is one of the most widely deployed protection and control relay architectures in global heavy industry. Installed across petrochemical complexes, nuclear generating stations, oil refineries, and high-voltage transmission substations, the UR platform provides modular, slot-based protection logic for generators, transformers, motors, buses, lines, and feeders. Its chassis-based architecture supports hot-swappable I/O modules, enabling maintenance without full system shutdown — a critical requirement in continuous-process industries. The UR6DV is a Digital I/O Input module within this platform, providing discrete contact sensing for protection logic and interlocking schemes.

The Evolution of UR Series Architecture

The UR platform was introduced by GE Multilin in the late 1990s as a successor to fixed-function electromechanical and early digital relays. The architecture is defined by a universal chassis (available in 3U, 5U, and 8U rack heights) populated with function-specific plug-in modules. Early UR generations used proprietary serial communications (RS-485, DNP3); subsequent revisions added IEC 61850 GOOSE messaging, IEEE 1588 precision time protocol, and fiber-optic inter-relay communications. The platform spans multiple product families — the C series (feeder/motor), D series (transformer differential), F series (feeder), G series (generator), L series (line distance), M series (motor), T series (transformer), and the universal chassis modules shared across all families. Compatibility between module generations is governed by firmware revision and chassis backplane version. Modules from early UR1 chassis are not electrically compatible with UR2 backplanes without adapter hardware. End-of-life announcements for select UR1-generation modules began in 2015, with GE (now GE Vernova / Grid Solutions) transitioning customers toward the UR2 and UR+ platforms. Long-term maintenance support for legacy UR1 modules is now primarily served by authorized third-party distributors and repair depots.

UR Series Full Catalog & Functionalities (SKU List)

The following SKUs represent verified, commonly stocked modules within the GE Multilin UR platform. Modules are categorized by functional type.

Digital I/O Modules

• UR6DV: 16-channel digital input module, dry contact sensing, universal relay chassis
• UR6CV: 16-channel digital output module, Form-C relay contacts, universal relay chassis
• UR6AV: 8-channel analog input module, 4–20 mA / 0–10 V, universal relay chassis
• UR6BV: 8-channel analog output module, 4–20 mA, universal relay chassis
• UR6EV: 4-channel RTD/thermocouple input module, universal relay chassis
• UR6FV: 4-channel fast digital input module, <1 ms response, universal relay chassis

CPU / Control Processor Modules

• UR9PH: Main CPU module, dual-core processor, IEC 61850 capable, UR2 platform
• UR9NH: CPU module with IEEE 1588 PTP, fiber Ethernet, UR2 platform
• UR9LH: Legacy CPU module, RS-485 DNP3, UR1 platform
• UR9KH: CPU module with redundant power input, UR1 platform

Communications Modules

• UR7AH: IEC 61850 GOOSE Ethernet communications module, dual-port fiber
• UR7BH: IEEE C37.94 multiplexed teleprotection communications module
• UR7CH: DNP3 / Modbus serial communications module, RS-485/RS-232
• UR7DH: Inter-relay communications module, direct fiber, <1 ms latency

Power Supply Modules

• UR8AH: 125/250 Vdc redundant power supply module, universal relay chassis
• UR8BH: 24/48 Vdc power supply module, universal relay chassis
• UR8CH: AC 120/240 V power supply module, universal relay chassis

Sourcing Hard-to-Find & Obsolete UR Series Parts

DriveKNMS maintains a dedicated inventory program for GE Multilin UR platform modules, with particular focus on UR1-generation hardware that has been discontinued by the OEM. For facilities operating legacy UR chassis in long-lifecycle environments — nuclear, refinery, or utility substation applications where full system replacement is not operationally feasible — DriveKNMS provides the following lifecycle extension services: verified surplus stock of discontinued SKUs including UR9LH, UR9KH, and early-generation I/O modules; factory-equivalent repair and refurbishment with full functional test; cross-reference and compatibility analysis between UR1 and UR2 module generations; and emergency same-day dispatch for critical plant maintenance windows. All sourced modules are accompanied by full traceability documentation and test records.

Quality Control for the UR Series Range

GE Multilin UR modules incorporate complex backplane bus communications and high-density FPGA-based protection logic that require specialized test procedures beyond standard power-on verification. DriveKNMS applies the following test protocol to all UR series modules prior to dispatch: backplane bus signal integrity verification using protocol-aware test fixtures; digital I/O channel-by-channel functional test under rated contact voltage (24 Vdc, 48 Vdc, 125 Vdc, 250 Vdc as applicable); analog I/O calibration verification against NIST-traceable reference instruments; CPU module firmware version identification and compatibility logging; communications module loopback test for all active ports (Ethernet, fiber, serial); and 48-hour burn-in under thermal cycling for refurbished units. Modules that do not pass all test stages are quarantined and not offered for sale.