Product pictures Product Overview: ABB SPAU140C Parameter Specification Manufacturer ABB Model SPAU140C Product Series SPACOM Protection Relays Device Type Numerical synchro-check relay Primary Function Synchro-check & voltage-check protection Application & Fault Scenarios Typical Uses: Monitors voltage, frequency, and phase angle between two power systems before closing a circuit breaker. Used in generator-to-grid synchronization, busbar paralleling, and transmission line