Specifications General Product Type: Automatic Transfer Switch (ATS) Series / Family: WATSN Automatic Transfer Switch Series Model: WATSN20/4A Number of Poles: 4 (three phases + neutral) Rated Current: 20 A Application: Automatic or manual transfer between two AC power sources in three‑phase distribution Electrical Ratings Rated Operational Voltage (Ue): Suitable for low‑voltage AC three‑phase systems (e.g., 400 V AC) Rated Frequency: 50/60 Hz Control Mode: Automatic transfer on detection of primary source failure, plus manual mode Switching Function: Ensures safe transfer of load between primary and alternate supply Operational Features Automatic Source Monitoring: Detects loss or abnormal conditions of primary supply and initiates transfer Manual Mode: Allows operator‑initiated transfer when automatic mode is disabled Position Indicator: Provides clear indication of current connection (primary/alternate/off) Modes Supported: Automatic transfer with reset, automatic transfer without reset, mutual standby Performance & Safety Utilization Category: Designed for low‑voltage distribution switching and isolation Electrical Isolation: Full disconnection of phases and neutral when in OFF position Control Logic: Integrated control for safe switching sequence and interlock between supplies Mechanical & Installation Mounting: Panel or switchboard installation Terminal Connections: Screw or clamp type terminals for secure conductor attachment Operating Conditions: Indoor electrical distribution environments Handle / Control: Front‑mounted control interface for mode selection and operation