ABB SPAD346 C3

ABB SPAD346 C3 is a rugged stabilized differential numerical protection relay from ABB legacy SPAD series, used for medium voltage transformer and generator differential protection. The stabilized differential numerical protection relay integrates transformer differential protection, three-stage overcurrent protection and multi-configurable earth fault protection. This stabilized differential numerical protection relay uses second harmonic restraint to avoid false operation caused by transformer inrush current, fifth harmonic restraint to prevent over-excitation mal-operation. The stabilized differential numerical protection relay has multiple programmable digital inputs and relay trip output contacts, panel mount design for marine & industrial MV switchboard cabinets.

This relay provides transformer & generator differential fault protection logic for medium voltage power networks. The transformer & generator differential fault protection logic continuously compares current signals on primary and secondary sides of transformer/generator. The transformer & generator differential fault protection logic discriminates internal winding short-circuit, inter-turn fault and external through faults. The transformer & generator differential fault protection logic triggers fast trip command to circuit breaker once detecting internal fault. The transformer & generator differential fault protection logic supports breaker failure protection, fault event recording and self-diagnosis for hardware and CT signal fault monitoring.

This ABB spare is an essential medium voltage power protection spare for vessel and industrial switchboard overhaul. The medium voltage power protection spare can replace damaged SPAD346 C3 protection relays directly. The medium voltage power protection spare meets IEC and marine classification society safety specifications. The medium voltage power protection spare is widely fitted on container ships, tankers and offshore platform medium voltage power distribution systems.

ABB SPAD346 C3 stabilized differential relay is classic legacy numerical protection device. It safeguards transformers and generators from winding short-circuit and earth faults, uses harmonic restraint to block inrush false tripping, performs reliably under heavy vibration and humid marine machinery room environments.