V-DOT VOLTAGE SENSORS

A V-dot voltage sensor is a derivative sensor designed to measure the rate of change of voltage over time (dV/dt) rather than the absolute voltage level. The sensor produces an output signal proportional to the time derivative of the voltage, which can then be integrated to reconstruct the original waveform. V-dot sensors are widely used in high-voltage and fast transient environments where conventional voltage probes cannot operate safely or accurately.

A V-dot sensor operates based on capacitive coupling. When placed near a conductor carrying a rapidly changing voltage, the electric field induces a current in the sensor proportional to the derivative of the voltage. Because the raw output represents dV/dt, the signal must pass through an integrator to reconstruct the original voltage waveform. This approach enables highly accurate measurements of very fast voltage transients while ensuring minimal loading of the circuit under test.

V-dot sensors capture signals with extremely high bandwidth, essential when analysing nanosecond or sub-nanosecond events. Because they rely on capacitive coupling, they are electrically isolated from the measured conductor, reducing safety risks and eliminating the need for direct connections in high-voltage environments. Unlike traditional probes, they provide a far more non-intrusive measurement method with minimal influence on the measured circuit.

Typical applications include pulsed power systems, high-voltage switching experiments, lightning impulse testing, electromagnetic compatibility (EMC) measurements, and defence or aerospace research. They are also valuable in laboratories studying electromagnetic pulse (EMP) effects, where accurate measurement of extremely fast voltage transients is required.

Montena V-dot sensors combine wide bandwidth, high sensitivity, and excellent signal fidelity. They are built with robust materials and optimised geometries for reliable operation in strong electromagnetic fields or high-voltage pulses. Their compatibility with dedicated integrators enables accurate reconstruction of voltage waveforms for analysis.