komponenttester

A komponenttester is a measurement device used to identify and characterize electronic components by applying known test signals and observing the response. They are commonly used by hobbyists, technicians, and engineers to verify components such as resistors, capacitors, inductors, diodes, and transistors. Devices range from pocket-sized handheld units to benchtop instruments and often include accessories for SMD components and test leads.

Common capabilities include measuring resistance, capacitance, inductance, and dielectric properties, as well as the equivalent series resistance (ESR) of capacitors and the equivalent series inductance (ESL) of inductors. Many testers also perform a diode check and provide transistor parameters such as gain (hFE) and type (NPN or PNP). Some models offer component identifier modes that attempt to determine a component's value or type automatically when the component is connected.

Technically, testers use various test methods, typically applying a small DC bias or an AC signal at a fixed frequency and then computing component values from the resulting voltage and current. Results are displayed on an LCD screen or transmitted to a computer or smartphone. In-circuit testing can be unreliable for some components; removal from the circuit or the use of test fixtures may be required for accurate measurements.

Open-source and DIY component testers have become popular, using microcontrollers and affordable sensors to provide basic measurements. While convenient, these devices may have limited accuracy, especially for very small capacitances or high-frequency components, compared with dedicated laboratory LCR meters.

See also: LCR meter, multimeter, transistor tester, electronic component testing, SMD testing.