GE UR81H Process Bus Module

Product Overview

The GE Multilin UR-81H is a specialized Process Bus Module and serves as a critical bridge between the primary substation equipment and the Universal Relay (UR) processor. Manufactured in Markham, Ontario, it is the only dedicated Process Bus module available for the UR series.

Technical Specifications

• Part Number: UR-81H

• Manufacturer: GE Multilin

• Manufacturing Location: Markham, Ontario, Canada

• Port Count: 8-Port Digital Interface

• Interface Type: Fiber Optic (Process Bus)

• Standards Compliance: IEC 61850-9-2LE / IEC 61869

• Weight: 1.15kg

• Dimensions: Approx. 6" L x 7" W x 1.5" H

Key Features and Engineering Advantages

• Digitized Data Acquisition: The UR-81H receives digitized streams from Merging Units (MUs) located at the primary equipment. This eliminates the need for long, expensive, and potentially hazardous analog copper runs into the control room.

• Universal Protocol Support: By adhering to international IEC standards, the UR-81H ensures that the data format is universal, allowing for interoperability between GE Multilin relays and third-party digital substation hardware.

• Simplified Hardware Profile: Because the UR-81H handles the data acquisition digitally, it reduces the need for multiple analog CT/VT modules within the relay chassis. Users can verify their system needs by checking the model number; those with "81" in the string already possess this advanced digital capability.

• Enhanced Safety: By replacing secondary CT circuits with fiber optics, the UR-81H eliminates the risk of "open-CT" high-voltage transients, which are a common safety concern in traditional substation environments.

• High-Density Monitoring: The eight-port configuration provides ample bandwidth for the relay to monitor multiple voltage and current streams simultaneously, supporting complex protection schemes like bus differential or transformer management.