Comprehensive Breaker Failure Protection
The SEL-352 offers circuit breaker failure protection, including failure to trip for fault or load conditions; failure to close, including pole disagreement; failure while open (flashover detection); failure to complete a trip or close due to stuck resistor switches; and loss of dielectric pressure. Five built-in schemes can be modified with SELogic control equations for application flexibility. Trip failure schemes accommodate single and multiple breaker applications, single-pole closing, and tripping applications. The breaker failure detection element includes unique subsidence current detection logic to provide fast reset after the breaker opens, providing decreased coordination delays for improved system stability.

Complete Breaker Control
Circuit breaker control features include MOD trip and power circuit breaker isolation security logic, retripping, point-on-wave and staggered phase closing, synchronism checking, and trapped-charge polarity detection for sophisticated breaker control. Extensive SELogic control equations allow you to create custom automatic reclosing schemes.

Data Recording
Data recording features include up to ten 60-cycle oscillographic event reports (64 samples/cycle), up to 512 SER reports, breaker trip and close monitor details, and a summary of electrical and mechanical operating times. Record accumulated breaker contact wear on per-phase basis. All recorded data are stored in nonvolatile memory.

High Reliability and Rugged Design
The SEL-352 withstands vibration, electrical surges, fast transients, and extreme temperatures, meeting stringent industry standards. For even harsher environments, order conformal coating for the printed circuit boards to provide an additional barrier to airborne contaminants, such as hydrogen sulfide, chlorine, salt, and moisture.