弱电电路地。
Weak electric circuit.
2. 代表大地或机箱的接地。
2. represents the grounding of the earth or the chassis.
3.中空的三角形通常表示数字接地，但是也常被作参考接地。
The 3. hollow triangle usually represents digital grounding, but is often referred to as grounding.
4. 三条向下递减的水平线代表模拟地或强电电路地。
4., three horizontal lines which are descending downward represent the analog or strong electric circuit.
3、地线的作用春晨FDES风力发电电缆耐扭转
3. The effect of the ground line
地线大家应该都知道，但是很多人不太明白这根线是做什么的，还有很多人在家庭改造线路是不把地线引起来，还自为得意的说，这样省了不少钱呢!在这我郑重的给大家说，这是严重的错误，下面为大家简单介绍一下地线的作用。 (1)供电地线，从变压器中性点接地后引出主干线，根据标准，每间隔20-30米重复接地，在电路中起安全保护作用。当人体触及到外壳已带电的电气设备时，由于接地体的接触电阻远小于人体电阻，绝大部分电流经接地体进入大地，只有很小部分流过人体，不致对人的生命造成危害。
The ground line everyone should know, but a lot of people do not know what this line is to do, there are many people in the family remolding line is not to lead to the ground line, but also to be proud to say, this saves a lot of money! In this I solemnly say, this is a serious mistake, the following is a simple introduction to the ground line. Use. (1) the main line is generated from the neutral point of the power supply ground. According to the standard, the ground is repeated at intervals of 20-30 meters, which plays a role of safety protection in the circuit. When the human body touches the electrified electrical equipment of the shell, because the contact resistance of the grounding body is far less than the resistance of the human body, the vast majority of the current enters the earth through the grounding body, only a small part of the body flows through the human body, and does not cause harm to the human life.
(2)电路地线，在电路设计时，( 电工之家)主要是防止干扰与提高无线电波的辐射效率。地线被广泛作为电位的参考点，为整个电路提供一个基准电位。此时，地线未必与真正的大地相连，而往往与输入电源线的一根相连，其电位也与大地电位无关。整个电路在设计时，以地线上电压为0V，以统一整个电路电位。
(2) when designing the circuit, the electrical home is mainly to prevent interference and improve the radiant efficiency of radio waves. Ground wire is widely used as a reference point for potential, providing a reference potential for the whole circuit. At this time, the ground wire may not be connected to the real earth, but often connected to the input power line, and its potential is also independent of the earth potential. When the whole circuit is designed, the voltage on the ground wire is 0V, so as to unify the whole circuit potential.春晨FDES风力发电电缆耐扭转
(3)用户地线，用来接单相220V的负载，传载单相电流和三相不平衡电流。
(3) user ground wire is used to load single phase 220V, carrying single-phase current and three-phase unbalanced current.
(4)工作地线，保证电气设备在正常和事故情况下可靠的工作，减小负载的中性点电位漂移。
(4) the working earth line ensures the reliable work of electrical equipment under normal and accident conditions, and reduces the neutral point potential drift of the load.
(5)在TN-C TN-C-S中还有接地和接零保护的功能。
(5) in TN-C TN-C-S, there are functions of grounding and zero protection.
