The SEL-352 Breaker Failure Relay provides breaker failure protection, breaker control, and breaker monitoring. Features include a cost-saving data recorder and a sophisticated breaker monitor and controller to reduce maintenance and supervise manual operations. SELogic control equations provide flexibility in applying the SEL-352 Relay for a variety of applications.
Breaker Failure Protection—Apply one SEL-352 per circuit breaker for single- or three-pole breaker failure detection. Detect failure to trip for fault or load conditions, failure to close, pole disagreement, failure while open (flashover detection), failure to trip or close due to stuck resistor switches, and loss of dielectric pressure. Overcurrent fault detection includes unique subsidence current logic to provide fast reset after the breaker opens.
Data Recording and Event Analysis—Record 10 seconds of oscillographic event reports, store up to 512 points of Sequential Events Recorder (SER) data, and monitor breaker trip and close operations, including accumulated interrupt current, and mechanical and electrical breaker operating times.
Configurable Circuit Breaker Control—Choose from five built-in schemes to cover ring-bus, breaker-and-a-half, or double-bus applications, or modify with SELogic control equations for custom applications. Sophisticated breaker control also includes Motor-Operated Disconnect (MOD) trip and power circuit breaker isolation security logic.
Point-on-Wave Opening and Closing Technology—Extend breaker life and reduce system transients and restrikes across opening and closing breaker contacts by implementing point-on-wave opening and closing technology.
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 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.