确切的建立电气是必要的continuitybetween two wires? If I want to have an electric current flow out of one wire and into another, what must be done with those two wires to make that flow path complete?
Conversely, what things might prevent continuity from being established between two wires when they are supposed to electrically connect with one another?
There must be metal-to-metal contact between the two wires in order to establish electrical continuity between the two. Anything preventing this clean contact between metal surfaces will inhibit continuity. This includes dirt, dust, oil, corrosion, misplaced insulation, and the like.
It might be helpful to show students what real pieces of wire look like, in order for them to better understand the nature of the problem. Most electrical wire is绝缘in one form or another, and this insulation must not be removed (or “stripped”) in order to establish bare metal-to-metal contact.
哪种类型的电测试将是检查两个导体之间电连接完整性的最直接方法？解释你的答案。
一个electricalresistancetest.
与您的学生讨论电气连接的理想阻力，无论类型（焊接，终端带，线条包裹，电线螺母，压接连接器等），在哪种条件下，您将测试电气连接的电阻。
一个有什么区别插头和杰克？这两个设备是用什么？绘制单核插头和插孔的示意图符号。
A “plug” is the male half of a temporary electrical connector, while the “jack” is the female half. Electrical connectors are used to make convenient connections between individual wires or sets of wires.
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Be sure to inform your students that poor electrical connections, often with regard to plug-and-jack assemblies, are averycommon source of failure in electrical andelectronic systems。
什么是a终端块， 或者接线板？How are these devices used to make electrical connections between different conductors?
端子“块”或“条”是用螺钉或其他紧固件设备的短而短的金属块，用于使导体机械键：
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有时，终端块也以“障碍条”的名称为单位。
请务必在讨论时间内有各种终端块供学生查看和触摸。终端块被广泛用于工业应用中，用于建立永久和半永久连接。
什么通常被认为是可以连接到终端块上单个端子的最大电线数？
每个紧固件两根电线，最大：
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我不确定是否有一个特定的代码或法规管理连接到终端块的终端数量，但是“每凸耳不超过两根线”规则很有意义。也就是说，当然，除非两个塞入同一孔中的导体将超过块的最大横截面面积极限，否则“不超过一线”是规则。
我的不幸在我的工作经历中看到了对这两个规则的严重侵犯！
电线螺母是住宅电源接线通常使用的特殊电气连接设备。描述什么是“电线螺母”以及如何使用电线之间的连接。
“金属丝螺母”是电气紧固件，使用盘绕的弹簧将裸金属线弯曲在一起。“螺母”被拧在两条或多个电线的末端，就好像它是螺母被螺母螺母上的。螺母内部弹簧的线圈作为螺纹的功能，当螺母顺时针方向上方转动螺母时，电线的末端更紧。
最好在课堂上有几种尺寸的电线螺母，让您的学生在讨论期间看到和触摸。
如何在插入组件的各个电线端之间建立连接印刷电路板（“ PCB”）？
Component wire ends are typically soldered onto strips of copper metal (called “traces”) affixed on the surface of the printed circuit board material, which itself is electrically insulating.
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Be sure to have a variety of printed circuit boards available for your students to see and touch during discussion time. PCBs are widely used in all varieties of electronic applications, and are well suited for mass production manufacturing techniques.
Suppose this circuit has a problem: the light bulb does not light up when the switch is turned “ON”. You suspect that a “bad” connection may exist in the circuit which is preventing current. How would you test the integrity of each connection using a voltmeter only?
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如果在两条电线的任何连接上测量电压，则该连接绝对是故障。
它可能更困难的首次出现test for voltage across any single connection, if the wires are covered with insulation! Ask your students this question: if you test for voltage between two screws on a terminal strip, how many electrical connections are you actually measuring voltage across?
Map the interconnections between holes in a typical无焊面包板，也通常被称为原始板：
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“映射”无焊面包板上的孔是一个有趣的练习，可以在欧姆米特尔（或任何其他形式的连续性指示器）中进行。
Show how to build a simple circuit consisting of a battery, a lamp, and a switch, mounting the lamp and switch on a无焊面包板(also known as a原始板):
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This is just one possibility - there are many others!
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无焊面包板是在教室/实验室环境中用于原型电路的极其有用的工具。熟悉它们的使用是任何现代电子课程的必要性。雷竞技最新app话虽这么说，但重要的是不要过分强调面包板。我已经看到了一些电子课程，其中面包雷竞技最新app板是有史以来巡回式建筑的唯一形式！这并不能为他们的工作挑战做好准备，那里的面包板仅用于原型制作。
In summary, use breadboards in your students’ labwork,但不是一直， 或者even most of the time!
什么是焊接ing？什么是焊接？
“焊接”是一种低温形式的焊接形式，通常用于将电导体连接在一起以进行永久连接。
“Solder” is a special alloy of metals designed to melt at a low temperature, to make permanent electrical connections.
应该注意的是，并非所有形式的焊接都是“低温”。例如，银焊发生在比常规电气焊接的温度更高的温度下进行。但是，所有焊接都是一种焊接形式。
一个alternative to焊接ing印刷电路板中的组件是使用一种称为的技术wire wrap。描述什么是“线条包裹”以及可能适合的应用。
“Wire wrap” is a connection technique for joining components together on a circuit board without need for pre-printed copper “traces” on the board. Instead, small-gauge wire is tightly wrapped around the pins of each component, with the wire making point-to-point connections between components.
尽管电线包裹现在并不像几十年前那样普遍，但它仍然具有某些应用的优点，特别是原型制作。如果可能的话，请在讨论时间内提供一些线包装的电路板，以向您的学生展示。
无焊面包板为电子爱好者，学生，技术人员和工程师提供方便的手段，以非永雷竞技最新app久形式建造电路。以下图表显示了在面包板上构建的三抗序列电路：
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面包板孔内的金属弹簧夹之间的互连可以使电阻的相邻导线之间的连续性，而不得不将电阻导线塞入同一孔中。
但是，新学生在首次学习如何使用无焊面包板时往往会陷入麻烦。这里显示了一个常见的错误，该学生试图创建一个简单的单耐电路：
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What the student has actually created here is ashort circuit。Re-draw this circuit in schematic form, and explain why this circuit is faulty.
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Follow-up question #1: explain what might happen if a large battery or high-current power supply were powering this short circuit.
后续问题2：展示单一驱动器电路如何should已经在面包板上建造，以避免短路。
这样的情况是very在新学生中常见！请务必讨论“短路”的意义以及如何避免它们。
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