Feature:  1. Automatic reset over‑voltage under‑voltage multi‑function protector is a monitoring and auxiliary protection device instrument suitable for three‑phase four‑wire power system or electrical equipment.  2. When the line has overvoltage, undervoltage, or overcurrent status, this product can instantly cut off the power supply to protect the electrical equipment from being damaged; when the line voltage returns to normal, the protector can automatically turn on the power supply normally.  3. This protector integrates over‑voltage protection, under‑voltage protection, over‑current protection, three‑phase current (voltage) unbalance protection, phase order protection (phase dislocation protection), and phase‑break protection in one.  4. The product has the function of fault inquiry, voltmeter and ammeter, and the function of restoring factory settings.  5. Adjustable voltage protector come with complete functions, stable performance and easy operation.    Specification:   Rated Voltage Three-Phase Four-Wire: 230V/400VAC 50/60Hz;  Current Rating: 50A, 63A, 80A(optional);  Overvoltage Protection Value Range: 221V-300V-OFF (default value 280V);  Overvoltage Recovery Value Range: 220V-299V (default value 250V);  Overvoltage Protection Action Time is Adjustable: 0.1 Seconds-10 seconds (default value is 0.2 seconds);  Undervoltage Protection Value Range: 219V-150V-OFF (default value 160V);  Undervoltage Recovery Value Range: 220V-151V (default value 180V);  Under Voltage Protection Action Time is Adjustable: 0.1 Seconds-10 seconds (default value 0.2 seconds);  Three-Phase Voltage Unbalance Protection Value Range: 10%-50%-OFF;  Phase Voltage Unbalance Protection Action Time: 0.1 seconds-10 seconds (default value 1.0 second);  Power-On Delay Time: 2-255 Seconds (default value is 2 seconds);  Failure Recovery Delay Time: 2-512 Seconds (default value is 60 seconds);  Display Mode: LCD;  Fault Indication: Segment character;  Sampling Method: AC sampling of phase line to neutral line resistance partial pressure;  Grounding System: TT, TN-S, TN-C-S;  Installation Method: Rail installation;  Electrical Isolation Strength: >2000VAC, pulse 2.5KV 1.2/50μS;  Working Environment: Temperature -20℃~50℃, Humidity＜85%, Altitude: No more than 2000meter;  Size: Approx. 72 x 80mm / 2.8 x 3.1in, 65mm / 2.6in, 43mm / 1.7in, 45mm / 1.8in, 35mm / 1.4in;    Package included:   1 x Adjustable Voltage Protector;  1 x User Manual