Introduction
iLEC ZCT (Zero Phase Current Transformer) tt is a specialized device used to detect leakage current or ground fault current by measuring the vector sum of three-phase currents.
1. Operating principleIn a normal electrical system, the total vector of the three-phase current is equal to 0.\(I_A + I_B + I_C = 0\)When a leakage current or ground fault occurs, an excess current (zero-sequence current) appears . The ZCT will detect this current and send a signal to the protective relay (EFR/ELR) to interrupt the circuit, protecting equipment and people.
2. Structure & ShapeShape: Typically toroidal (round) in design, the system's phase/neutral wire is threaded through the circular hole in the center of the sensor.Characteristics: Unlike conventional CTs, it does not have a fixed current transformation ratio but operates based on the principle of direct magnetic induction of the total current flowing through the center.
3. Main functionsLeakage protection: Prevents the risk of electric shock when people accidentally touch equipment with a faulty electrical connection.Ground fault protection: Detects and disconnects the system in the event of a phase short circuit to the equipment casing, protecting cables and equipment from fire and explosion.
4. Practical applicationsCommonly installed in industrial electrical cabinets and main distribution boards (MSBs), in combination with ground fault and leakage protection relays (such as Mikro, Schneider, Omron relays, etc.).To learn more about the detailed operation or to select the appropriate leakage current range for your system, you can refer to the manufacturer's documentation for the Mikro ZCT zero-sequence current transformer to choose the most accurate measuring devices.