Description: Application: This voltage protection relay features overvoltage, under-voltage, phase loss, phase dislocation, voltage unbalance protection and fault record function. Free to adjust: This under over voltage protector features 390-490v overvoltage range and 300-370V under-voltage range, meeting your different needs. Easy to read: This voltage protection relay is designed with an LCD screen to display voltage, fault statues, and other parameters, so you can easily know everything. Simple to install: This under over voltage protective device is designed for 35mm guide rail and requires no additional assistant power supplies. Wide usage: This voltage protector is widely applied to an electric motor, air conditioner, ventilator, water pump, compressor, and so on. Specification: Circuit: L1, L2, L3. Rated voltage: 380VAC, 50Hz. Overvoltage adjustment range: 390-490V. Under-voltage adjustment range: 300-370V. Overvoltage and under-voltage recovery return difference: 10V. Overvoltage and under-voltage action time: 0.1-25s. Three-phase unbalance adjustment range: 5%-29%. Three-phase unbalanced action time: 1-25s. Phase loss action time: 1s. Phase dislocation action time: Instant. Display mode: LCD. Contact form: one set of constant open, one set of constant closed. Contact capacity: 6A AC250V (Resistive). Size(LxWxH): Approx. 80x43x54mm/3.15x1.69x2.13 inch. Installation method: 35mm guide rail. Note: This product is for 3-phase power sampling. Do not install it on the AC power output. Package Includes: 1 Piece LCD Voltage Protector.