An Uninterruptible Power System as a Safety Related Isolation Device for Nuclear Power Plants

This paper describes the test procedure and results of a program to qualify a Class 1E uninterruptible power supply (UPS) as a power circuit isolation device between Class 1E power input sources and non-Class 1E load circuits for application in a nuclear power plant. Results demonstrate that the tested equipment provides suitable isolation and that the UPS is completely self-protecting as well as providing its normal UPS functions with automatic static bypass in the event of UPS failure or externally applied overload.