BENTELY 128229-01 数字输入模块（DI）32к通道2MLI-D24A

BENTELY 128229-01 数字输入模块（DI）32к通道2MLI-D24A

电源变压器的屏蔽层：静电屏蔽层应接到保护地。

为了保证电缆屏蔽层真正实现一点接地，应该注意以下事项：

1) 屏蔽电缆要有绝缘护套；敷设安装电缆时避免损坏护套，譬如不可在有尖锐边缘的金属部位拖拉电缆；屏蔽层经过转接端子时，须专门配备供屏蔽层用的专用端子，图3.2.2-1所示，这样能保持屏蔽层的连续性。

2) 当发现屏蔽接地效果不佳时，首先要检查屏蔽层的绝缘护套是否损坏。判断的方法是：将屏蔽地一点接地点断开，检查屏蔽效果是否有改善，若是，则可以判断电缆护套可能损坏。

3) 对个别情况，信号电缆的屏蔽层需要两端接地。如某些灵敏的高频输入电缆层要采用两端接地，而且电缆应紧贴地面敷设，以减少接地环路的面积；当地电位差较大时，还可紧靠屏蔽线敷设一根较粗的电位平衡导线来平衡地电位差，减少流入屏蔽层的电流。

BENTELY 128229-01 数字输入模块（DI）32к通道2MLI-D24A

Shielding layer of power transformer: electrostatic shielding layer should be connected to the protection ground.

In order to ensure that the cable shield layer is truly grounded, the following matters should be noted:

1) The shielded cable should have an insulating sheath; Avoid damaging the sheath when laying and installing the cable, for example, do not drag the cable in the metal part with a sharp edge; When the shielding layer passes through the conversion terminal, special terminals must be equipped for the shielding layer, as shown in Figure 3.2.2-1, so as to maintain the continuity of the shielding layer.

2) When it is found that the shielding grounding effect is not good, first check whether the insulating sheath of the shielding layer is damaged. The method of judgment is: disconnect the ground point of the shielding ground, check whether the shielding effect is improved, if it is, you can judge that the cable sheath may be damaged.

3) For individual cases, the shielding layer of the signal cable needs to be grounded at both ends. For example, some sensitive high-frequency input cable layers should be grounded at both ends, and the cable should be laid close to the ground to reduce the area of the grounding loop; When the potential difference is large, a thicker potential balancing wire can also be laid close to the shield line to balance the ground potential difference and reduce the current flowing into the shield layer.

BENTELY 128229-01 数字输入模块（DI）32к通道2MLI-D24A