Adopting special transient-control component and scientific design, as well as taking advantage of standard pot-like capacitance, the power saver improve power-factor in sensitive-system by adding capacitance. Strong and weak current of power-supply network is able to balance each other, restrain different voltage, leach transient-surge effectively in circuit, rise efficiency of equipment operation, improve life-span of device through the effect of special circuit, with function of saving electricity, protecting equipment and improving the condition of environment.