YC9VA Voltage Protection Relay

The YC9VA is a microprocessor-based voltage and current display relay designed for AC networks (50-60 Hz). It protects electrical equipment from overvoltage and undervoltage conditions by monitoring main voltage and disconnecting the load via an electromagnetic relay. The device features a digital display showing real-time voltage (and current in supported versions), user-adjustable overvoltage and undervoltage settings, delay times via buttons, and non-volatile memory to store settings. It supports both copper and aluminum wiring connections. The insulation voltage is rated around 450V in some versions, and the protection rating is IP20. Available current adjustment ranges in some models are between 5A and 63A.