U.S. NRC Experience with Undervoltage Trip Attachments on Reactor Trip Switchgear
An overview of the failures of reactor trip switchgear to trip soley on loss of voltage is presented. There are three types of switchgear in reactor protection systems in pressurized water reactors in the United States. The review of the failures to date and the corrective actions taken suggest that proper maintenance and surveillance testing of existing undervoltage trip attachments on reactor trip switchgear should reduce substantially the number of failures.
UNITED STATES NUCLEAR REGULATORY COMMISSION REGION II
Northern States Power Company, a Minnesota corporation, requests authorization for changes to Appendix A of the Monticello Operating License as shown on the attachments labeled Exhibits A, and B. Exhibit A describes the proposed changes, describes the reasons for the changes, and contains a significant hazards evaluation. Exhibit B is a copy of the Monticello Technical Specifications incorporating the proposed changes.
Simulating the Illuminance and Efficiency of the LEDs Used in General Household Lighting
Abstract The advantage of the LEDs illumination in general household lighting was proposed. High efficiency white LED as the light source was provided the energy saving illumination of the general household lightings. Different spaces in general household with different standards of average illuminance were designed and simulated by LightTools and DIALux software. The power consumptions and efficiency of traditional illuminated light sources and LED light source in lighting the household environment were analyzed and compared with each other at the same standard of average illuminance. Finally, it provided the advantage of using white LEDs in different spaces of the general household lighting.