Capacitance and Inductance Tester, also known as LCR Tester, is an electronic measuring instrument used for precise measurement of key parameters of passive components such as inductance



(L), capacitance (C), and resistance (R).

According to different application scenarios, it is mainly divided into two categories: one is specialized equipment for on-site power system testing of large reactive power compensation devices without disconnecting wires; the other is a precision LCR digital bridge for R&D, production, and quality inspection of electronic components.

⚡ Power System Specialized Type (Non-disconnect Testing)

This type of instrument is specially designed for on-site environments such as substations and power plants. Its core advantage is that it can directly measure the capacitance value of a single capacitor in a parallel capacitor bank without removing the busbar, greatly improving work efficiency and safety.

Working Principle

The instrument internally generates a power frequency (50Hz) AC test voltage (e.g., 20V), which is applied to the busbars at both poles of the capacitor bank through test leads. At the same time, a high-precision clamp current transformer (CT) is clamped onto the lead of the capacitor under test to measure the current flowing through it. The instrument calculates the capacitance using the formula Cx = Ic / (2πfU) based on the measured voltage (U) and current (Ic).

Core Applications

Detection of reactive power compensation capacitor banks: Quickly determine whether any individual capacitor in a parallel capacitor bank is damaged (e.g., capacitance decay, open circuit, or short circuit) without power outage or wire disconnection.

Inductance measurement of reactors: Measure the inductance of series or parallel reactors.

Other measurements: Some models also support resistance measurement (e.g., ground down-conductor continuity test) and power frequency current measurement.

Main Features

Non-disconnect measurement: The biggest feature, saving a lot of manpower and time.

Strong anti-interference capability: Designed for on-site environments with strong electromagnetic interference, providing stable and reliable measurement results.

Portable and easy to use: Usually adopts a portable design, equipped with a large LCD screen and Chinese menu, simple operation.

Data management: Built-in memory can save multiple sets of data, and reports can be printed on-site via a micro thermal printer; some high-end models support USB export.