信號線英語怎麼說及英文翻譯

A. 求翻譯，英譯漢，高手們幫幫忙啊。

No exposed powered electrical connections/terminations are permitted in any external or internal part of the system.
該系統內外不得出現任何裸露的帶電接頭/端子。

Suitable cables creening must be used where necessary for power, control and signal cables.
如有必要，電源線、控制線、信號線需進行適當屏蔽。

All power cables must be isolated from control and signal cables.
所有電源線需與控制線和信號線隔離。

All power and signal cables must be isolated from one another and all other services.

所有電源線和信號線必須根據各自用途彼此隔離。（這一句英文原文可能有問題！）