Bilingual edition: English is preserved and Chinese follows each unit. Terminology uses the confirmed v20260916 glossary; automated semantic review remains traceable.
中英双语版：英文原文完整保留，中文紧随对应单元；术语采用 v20260916 确认表，自动语义审校结果可追溯。

Moving Coil Meters

动圈检流计

The design of a voltmeter, ammeter or ohmmeter begins with a current-sensitive element. Though most modern meters have solid state digital readouts, the physics is more readily demonstrated with a moving coil current detector called a galvanometer. Since the modifications of the current sensor are compact, it is practical to have all three functions in a single instrument with multiple ranges of sensitivity. Schematically, a single range "multimeter" might be designed as illustrated.

电压表、电流表或欧姆表的设计始于一个对电流敏感的元件。尽管大多数现代仪表都有固体状态的数字显示，但用移动线圈电流检测器（称为检流计）来展示其物理原理更为直观。由于电流传感器的修改较为紧凑，将三种功能集成于一个仪器中，并具有多个灵敏度范围是可行的。图示中，一个单量程的“万用表”可能被设计成如下所示。
Voltmeter design
电压表设计
Ammeter design
安培计设计
Ohmmeter design
欧姆计设计
Voltmeter/Ammeter measurements of resistance
伏特计/安培计测量电阻
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Voltmeter

电压表
A voltmeter measures the change in voltage between two points in an electric circuit and therefore must be connected in parallel with the portion of the circuit on which the measurement is made. By contrast, an ammeter must be connected in series. In analogy with a water circuit, a voltmeter is like a meter designed to measure pressure difference. It is necessary for the voltmeter to have a very high resistance so that it does not have an appreciable affect on the current or voltage associated with the measured circuit. Modern solid-state meters have digital readouts, but the principles of operation can be better appreciated by examining the older moving coil meters based on galvanometer sensors.
Details of voltmeter design
电压表设计细节
电压表测量电路中两点之间的电压变化，因此必须与所测电路部分并联连接。相比之下，电流表必须串联连接。类比于水路，电压表就像一个用来测量压力差的仪表。为了不显著影响所测电路的电流或电压，电压表必须具有非常高的电阻。现代固态仪表具有数字显示，但通过研究基于检流计传感器的旧式活动线圈仪表，可以更好地理解其工作原理。
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Ammeter

安培计

An ammeter is an instrument for measuring the electric current in amperes in a branch of an electric circuit. It must be placed in series with the measured branch, and must have very low resistance to avoid significant alteration of the current it is to measure. By contrast, an voltmeter must be connected in parallel. The analogy with an in-line flowmeter in a water circuit can help visualize why an ammeter must have a low resistance, and why connecting an ammeter in parallel can damage the meter. Modern solid-state meters have digital readouts, but the principles of operation can be better appreciated by examining the older moving coil meters based on galvanometer sensors.

电流表是一种用于测量电路中某一支路电流（单位为安培）的仪器。它必须串联在被测支路中，并且必须具有非常低的电阻，以避免显著改变其测量的电流。相比之下，电压表必须并联连接。通过类比水力系统中的直通流量计，可以帮助理解为什么电流表必须具有低电阻，以及为什么将电流表并联连接会损坏仪表。现代固态仪表具有数字显示，但通过研究基于检流计传感器的旧式动圈仪表，可以更好地理解其工作原理。
Details about ammeter design
电流表设计细节
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Ohmmeter

欧姆计

The standard way to measure resistance in ohms is to supply a constant voltage to the resistance and measure the current through it. That current is of course inversely proportional to the resistance according to Ohm's law, so that you have a non-linear scale. The current registered by the current sensing element is proportional to 1/R, so that a large current implies a small resistance. Modern solid-state meters have digital readouts, but the principles of operation can be better appreciated by examining the older moving coil meters based on galvanometer sensors.

用欧姆来测量电阻的标准方法是向电阻施加恒定电压并测量通过它的电流。根据欧姆定律，电流显然与电阻成反比，因此你得到的是一条非线性刻度。电流传感元件所记录的电流与1/R成正比，因此大电流意味着小电阻。现代固态仪表具有数字显示，但通过研究基于检流计传感器的旧式动圈仪表，可以更好地理解其工作原理。
Voltmeter/Ammeter measurements of resistance
伏特计/安培计测量电阻
 Index

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Voltmeter/Ammeter Measurements

电压表/电流表测量

The value of electrical resistance associated with a circuit element or appliance can be determined by measuring the voltage across it with a voltmeter and the current through it with an ammeter and then dividing the measured voltage by the current. This is an application of Ohm's law, but this method works even for non-ohmic resistances where the resistance might depend upon the current. At least in those cases it gives you the effective resistance in ohms under that specific combination of voltage and current.

与电路元件或电器相关的电导值可以通过用电压表测量其两端的电压，用电流表测量通过它的电流，然后将测得的电压除以电流来确定。这是欧姆定律的应用，但这种方法即使在非欧姆电阻的情况下也适用，其中电阻可能取决于电流。至少在这些情况下，它能给出在特定电压和电流组合下的有效电阻（单位为欧姆）。
For
对于
 V = volts and I = A, then RL =Ω
当电压V以伏特为单位，电流I以安培为单位时，电阻R_L的单位是欧姆。
中文译文中的待填/计算数值依次对应：1：v1 2：i1 3：r1。实际数值以上方原输入框为准。
For
对于
 V = volts and I = mA, then RL =KΩ
当电压V以伏特为单位，电流I以毫安为单位时，电阻R_L为千欧。
中文译文中的待填/计算数值依次对应：1：v2 2：i2 3：r2。实际数值以上方原输入框为准。
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