"220V Cooling Fan" module power supply design, not only to select the correct input, output and reasonable, appropriate load current, but also to consider how to avoid oscillation system, the emergence of various interference power to make adjustments performance deterioration, noise increases as well as a ground fault circuit, cooling capacity is not enough other issues. Here are some action against these problems. "220V Cooling Fan" to improve the loading effect of the load effect to characterize the degree of influence of load changes the output voltage of the power supply. Wire contact resistance and contact resistance between the power source and the load is smaller, the smaller the impact on the loading effect. When the load current is large, a small wire resistance and contact resistance will have a significant effect on the loading effect, so a lot of high-current power supply in a pair of internal adjustment terminals called telemetry end sampling network circuit. "220V Cooling Fan" telemetry using the voltage across the load terminals can be directly detected, reducing the effects of lead resistance load effects.