YPK111A YT204001-HH ABB

It is generally required that the signal line must have a unique reference ground.When the shielded cable encounters occasions where conducted interference may occur,it should also be uniquely grounded on the spot or in the control room to prevent the formation of”ground loops”.When the signal source is grounded,the shielding layer should be grounded on the signal side;when it is not grounded,it should be grounded on the PLC side;when there is a connector in the middle of the signal line,the shielding layer should be firmly connected and insulated,and multi-point grounding must be avoided;When the shielded twisted pair of the point signal is connected with the multi-core twisted pair overall shielded cable,the shielding layers should be well connected to each other,and after insulation treatment,select an appropriate single-point contact at the grounding point.

一般要求信号线必须要有唯一的参考地，屏蔽电缆遇到有可能产生传导干扰的场合，也要在就地或者控制室唯一接地，防止形成“地环路”。信号源接地时，屏蔽层应在信号侧接地；不接地时，应在PLC侧接地；信号线中间有接头时，屏蔽层应牢固连接并进行绝缘处理，一定要避免多点接地；多个测点信号的屏蔽双绞线与多芯对绞总屏蔽电缆连接时，各屏蔽层应相互连接好，并经绝缘处理，选择适当的接地处单点接点。