SPAU 140 C Synchro-Check Relay User Manual and Technical Description

This document is a user manual and technical description for the SPAU 140 C synchro-check relay, a microprocessor-based voltage measuring relay used to verify conditions for circuit breaker closing, including synchronism and voltage checks. It covers features, application, operation, connection diagrams, technical data, commissioning, and maintenance for the relay and its associated SPCU 3D45 module.