GE UR Series Modules UR 9GH Universal Relay CPU

Technical Dossier

Product Details And Specifications

GE UR Series Technical Notes

The GE UR (Universal Relay) platform, developed by GE Grid Solutions (formerly GE Multilin), is one of the most widely deployed digital protection relay architectures in global heavy industry. UR-series relays are installed across high-voltage substations, chemical processing plants, nuclear generating stations, offshore oil platforms, and petroleum refineries on every continent. The platform's modular hardware architecture — where CPU, I/O, power supply, and communications modules slot into a common chassis — has made it the reference standard for utility-grade protection, control, and monitoring applications since its commercial introduction in the late 1990s. Its IEC 61850 compliance, dual-redundant Ethernet capability, and NERC CIP-compatible cybersecurity features have sustained its specification in new-build and retrofit projects well into the 2020s.

The Evolution of UR Series Architecture

The UR platform launched with the D60 Line Distance Relay and T60 Transformer Protection Relay as its first commercial products, establishing the 8-slot and 14-slot horizontal chassis form factors that remain in production today. Early firmware (pre-4.0x) used a proprietary EnerVista UR Setup communications stack over RS-485 and RS-232 serial interfaces. The transition to firmware 5.x introduced IEC 61850 Edition 1 GOOSE messaging and MMS protocol support, enabling peer-to-peer tripping without hardwired contacts — a critical capability for modern digital substation architectures.

Firmware 7.x added IEC 61850 Edition 2 compliance, IEEE 1588 Precision Time Protocol (PTP) for microsecond-accurate time synchronization, and enhanced cybersecurity aligned with NERC CIP-007. The introduction of the 9-series CPU modules (including the UR 9GH) represented a hardware generation upgrade: faster DSP processing, expanded FlexLogic equation capacity, and support for higher-density I/O configurations. Compatibility between 7-series and 9-series CPUs within the same chassis requires firmware alignment and should be verified against GE's UR Hardware Compatibility Matrix before field substitution.

For installations running firmware below 5.x, direct upgrade paths to 7.x or 9.x-compatible firmware may require intermediate steps and hardware assessment. DriveKNMS maintains a compatibility cross-reference database for UR CPU module substitutions across all firmware generations.

UR Series Full Catalog & Functionalities (SKU List)

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

CPU & Processing Modules

• UR 9GH: High-capacity CPU module, 9-series, dual Ethernet, IEEE 1588 PTP support
• UR 9G: Standard 9-series CPU, single Ethernet port, core FlexLogic processing
• UR 7H: 7-series CPU, dual Ethernet, IEC 61850 Ed.2, legacy chassis compatible
• UR 7G: 7-series CPU, single Ethernet, standard protection relay processing
• UR 6H: 6-series CPU, dual-port Ethernet, IEC 61850 Ed.1, mid-generation platform

Digital Input (DI) Modules

• UR 8D: 24-channel digital input module, 24–250 VDC/VAC wet contact sensing
• UR 8E: 16-channel digital input, high-speed optocoupler isolation, 125 VDC nominal
• UR 8F: 32-channel digital input, extended voltage range, DIN rail compatible

Digital Output (DO) / Relay Output Modules

• UR 8L: 16-channel form-A relay output, 30 A make / 8 A carry, trip-rated contacts
• UR 8M: 8-channel form-C relay output, high-current interrupting capacity
• UR 8N: 24-channel solid-state output module, fast operate time <1 ms

Analog Input (AI) Modules

• UR 8A: 8-channel CT/VT analog input, 1 A / 5 A CT selectable, 100–240 VAC VT input
• UR 8B: 4-channel transducer input, 4–20 mA / 0–10 V, for RTD and process signals
• UR 8C: 16-channel analog input, mixed CT/VT and transducer configuration

Communications & Networking Modules

• UR 9C: Dual-port fiber Ethernet communications module, 100BASE-FX, IEC 61850 GOOSE
• UR 9D: IEEE C37.94 teleprotection interface module, 64 kbps multiplexed channel
• UR 8K: RS-485 / RS-232 serial communications module, DNP3 and Modbus RTU

Power Supply Modules

• UR 9P: 125/250 VDC station battery power supply, redundant input capable
• UR 9Q: 24/48 VDC low-voltage power supply module, telecom substation applications

Sourcing Hard-to-Find & Obsolete UR Series Parts

GE Grid Solutions has progressively transitioned earlier UR hardware generations (5-series, 6-series) to end-of-active-support status. For substations and industrial facilities operating on long asset lifecycles — common in nuclear, hydro, and petrochemical environments — replacement modules for these generations are no longer available through standard OEM distribution channels.

Quality Control for the UR Series Range

UR series modules present specific test challenges due to their integrated backplane bus architecture and firmware-dependent initialization sequences. DriveKNMS applies the following verification protocol to all UR modules prior to dispatch: