klämameter

A klämameter, also known as a clamp meter, is a portable electrical measuring instrument designed to measure current without requiring the circuit to be opened or disconnected. It features a hinged or spring-loaded jaw that clamps around a single conductor. Inside, a current transformer detects the magnetic field generated by the conductor; the secondary winding provides a signal proportional to the current flowing through the conductor, which is displayed on a digital readout. Modern clamp meters often include additional measurement capabilities and electronic features.

Most digital klämameter can measure alternating current (AC) and, in many models, direct current (DC). They may also measure AC voltage, resistance, continuity, frequency, and, in advanced units, parameters such as power factor, impedance, and temperature. Many devices offer true RMS measurements to improve accuracy with non-sinusoidal waveforms. Convenience features frequently found on contemporary meters include auto-ranging, data hold, min/max recording, relative (zero) mode, and wireless data transfer via Bluetooth or USB.

Applications and use: clamp meters are widely used by electricians, technicians, and engineers for troubleshooting electrical installations, verifying loads, and conducting energy audits. The non-contact measurement capability allows assessment without interrupting circuits, reducing downtime and risk.

Limitations and safety: accurate use requires clamping around a single conductor; enclosing multiple conductors or conductors carrying opposite currents can yield erroneous readings. Some meters measure only AC current, while others support DC. High currents can saturate the core and reduce accuracy. Proper safety practices and appropriate CAT ratings for the voltage level are essential during use.