Extending the Life of Obsolete Power Supplies: NES Successfully Refurbishes Critical Nuclear Electronics

Nuclear Electronic Solutions (NES) recently completed a refurbishment project for one of our nuclear industry clients, focusing on the repair and refurbishment of two obsolete Power-Mate power supplies. These units are critical for providing 10 VDC to the electronics that monitor and control the Control Element Drive Mechanism Control System (CEDMCS). The power supplies had a significant issue limiting their output voltage that prevented them from reaching the required maximum output voltage. Complicating matters, these units are no longer available or supported by the original equipment manufacturer (OEM).

Rather than undertaking a costly and complex engineering redesign to replace the units with modern alternatives, our client entrusted NES to resolve the issue. Upon receiving the units, our skilled technicians and engineers conducted a thorough incoming inspection and performance review, during which they identified a high ripple voltage on the output—a condition that could lead to functional issues with downstream electronics.

To address this, NES performed an engineering analysis to identify modern, compatible components for the power supply. Once identified, these components were sourced from one of our trusted vendors, rigorously inspected, and then installed. The updated components successfully resolved the ripple issue and exceeded the original performance specifications.

In addition to this, NES engineering staff conducted an in-depth analysis of the power supply circuitry to rectify the voltage output and range adjustment issues. The analysis determined that replacing the existing potentiometer with one offering a broader resistance range was necessary to meet the nuclear facility's requirements. After an extensive search, a suitable replacement was identified, installed by our technicians, and subjected to comprehensive testing. The upgraded units performed exceptionally well, meeting and exceeding all performance specifications.

As the final step, the units underwent a 100-hour burn-in at 50% load, followed by post burn-in electrical verifications. Both units not only met but also surpassed the performance criteria and were promptly returned to our client.

This project is a testament to NES's ability to extend the life of obsolete electronics, delivering significant resource savings and reducing plant risks for our clients. NES continues to add value by providing innovative solutions that ensure the reliability and longevity of critical nuclear systems.