SVP sequence automated over-voltage and under-voltage protector is appropriate for single-phase 220V, 50/60Hz, rated operating recent 40A or 63A or 80A or much less lots It is principally used for residential household field access or over-voltage, under-voltage or over-current defense of distribution lines for single-phase electric kit Its main characteristic is when the circuit has over-voltage or under-voltage, over-current problems, the product can bring to an end the power delivery instantaneously to protect the electrical kit from being damaged, besides,the protector can mechanically switch on the ability delivery when the circuit voltage returns to the conventional The green indicator display, when the power is typical supply The pink indicator display, when the ability over voltage or below voltage Functions: 1 Over-voltage protection 2 Under-voltage protection three Over-current defense 4 Automatic recovery 5 Voltage display(voltage measurement) 6 Current display (current measurement) Noted: When you first join the product, you need to wait about 1 minute, after the pink mild flip off, then the product will work The model 63A and 80A , it displays in two colours (Red and Green)