The GE Multilin UR9AH is a standard-capacity Power Supply Module designed for the Universal Relay (UR) series of protective relaying and control devices. As the primary energy source for the relay’s internal electronics, the UR9AH converts substation or industrial station power into the regulated DC voltages necessary to operate the CPU, I/O modules, and communication cards. The “9AH” designation identifies this as a High-Voltage (H) variant, capable of accepting a wide range of AC and DC inputs. Unlike the UR6 series power supplies which are often used in smaller or older chassis, the UR9AH is optimized for modern UR chassis configurations where reliable, continuous operation is required for critical protection functions like bus, feeder, or transformer management.
Technical Specifications
The following technical parameters define the UR9AH power supply module:
- Model Number: UR9AH
- Manufacturer: GE Multilin (General Electric)
- Series: Universal Relay (UR) Series (compatible with B90, C90, G90, etc.)
- Input Voltage Range: 125 – 250 V DC or 120 – 240 V AC
- Output Capacity: Standard output for UR internal buses
- Ride-through Time: 100 ms (minimum) at nominal input voltage
- Efficiency: >80% at full load
- Isolation: 2.3 kV AC dielectric strength (Input to Chassis)
- Dimensions: 180mm x 45mm x 250mm
- Operating Temperature: -40°C to +60°C
Application Fields
The UR9AH is a foundational component in GE Multilin UR-series architectures, including:
- Substation Protection: Providing stable power for feeder (F60), bus (B90), and transformer (T60) relays.
- Generator Control: Supporting G60 and G30 units in large power plants to ensure uninterrupted monitoring.
- Transmission Systems: Powering D60 distance protection and L90 line differential protection systems.
- Heavy Industry: Integrated into power management systems for mining, oil and gas, and chemical processing plants where station battery systems provide high-voltage DC power.
Product Instructions and Handling
The UR9AH module is designed to slide into the dedicated power supply slot (typically Slot P1) of a UR chassis. Before installation, confirm that the input power source matches the “H” (High Voltage) rating of 125-250V DC or 120-240V AC. Ensure the module is pushed fully into the backplane connectors and that the front-panel thumbscrews are tightened to provide a secure mechanical and ground connection. Because this module interfaces with high-energy station power, all wiring should be handled by qualified personnel with the source disconnected. To protect the sensitive power electronics and onboard logic, always use a grounded ESD wrist strap when handling the module and avoid touching the rear connector pins.
Questions and Answers
Q: What is the difference between the UR9AH and the UR6UH? A: Both are high-voltage power supplies. However, the UR9AH is generally associated with newer hardware revisions and specific chassis sizes within the UR family. While they often serve the same function, you should check your specific relay’s “Order Code” to ensure physical and firmware compatibility.
Q: Does the UR9AH support redundant power supply configurations? A: Many UR-series chassis allow for a second power supply module (Redundant Power Supply option). In such cases, a UR9AH can work in tandem with another identical module to ensure the relay stays online if one power source or module fails.
Q: How can I tell if the UR9AH module is functioning correctly? A: A healthy module will allow the relay to complete its boot sequence. If the module fails, the relay’s “Critical Fail” LED will illuminate, and the self-diagnostic logs will flag a “Power Supply Error.”
Product Related News: Ensuring Reliability in Critical Infrastructure
As power utilities transition toward the “Digital Substation” and IEC 61850 standards, the role of robust power supplies like the GE Multilin UR9AH remains paramount. Even as logic and communication become more advanced, the physical reliability of the power source is the single most common point of failure in protection systems. Recent industry maintenance trends highlight that power supplies are the “wear items” of the relay world due to constant thermal stress. By maintaining a stock of original UR9AH modules, plant operators can minimize downtime during routine maintenance or emergency repairs, ensuring that their protection, control, and data acquisition assets remain active and compliant with NERC/CIP reliability mandates.
