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4.屏蔽设计电屏蔽。电屏蔽是切断电容性电磁耦合的一种措施。一般使用在变压器绕组之间屏蔽、印刷电路板线路的屏蔽以及电缆线屏蔽等场合。良好的电屏蔽设计,应保证电屏蔽体必须有良好的接地,否则干扰比不加电屏蔽前更严重。一般要求屏蔽体与地的接触电阻小于2毫欧,在严格场合要求小于0.5毫欧,并且应使屏蔽体的接地点靠近被屏蔽元件的入地点。为了减少剩余电容,对屏蔽体的形状应有要求,屏蔽体做成壳体比平板要好,密封壳体比开窗孔的壳体好。例如变压器初次级间电屏蔽效果,封闭优于外折屏蔽、外折屏蔽优于带状屏蔽。
4. Shield design electric shielding. Electrical shielding is a measure to cut off capacitive electromagnetic coupling. General use in the shield between the transformer windings, printed circuit board line shielding and cable shielding and other occasions. Good electrical shielding design, should ensure that the electrical shielding must have a good grounding, or interference than without electricity shielding more serious. The general requirements of the shield and the ground contact resistance of less than 2 milliohms, less than 0.5 milliohms in strict occasions, and should shield the grounding point near the shielded component into the site. In order to reduce the remaining capacitance, the shape of the shield should be required, the shield made of the housing is better than the flat, the sealed housing is better than the opening of the housing. For example, the primary electrical transformer between the shielding effect, closure is better than the outer folded shield, outer folded shield is better than the strip shield.