spanningsval

Spanningsval, or voltage drop, is the decrease in voltage between a source and a point in an electrical circuit. It occurs whenever current flows through impedances such as conductor resistance, contact resistance, and the impedance of the connected components. The concept covers both the static reduction due to series impedances and dynamic fluctuations caused by changing loads or supply conditions.

In DC circuits, the voltage drop along a conductor or across a component is described by Ohm’s law as V_drop = I × R, where I is the current and R is the resistance in the path. In AC circuits, especially with inductive or capacitive elements, the drop is V_drop = I × Z, where Z is a complex impedance. For circuits with multiple series elements, the voltage division principle applies, and the voltage across each element depends on its share of the total impedance.

Common causes include long wiring runs, small conductor cross-sections, poor connections, and regulators or power supplies with limited output under load. Temperature, aging, and multi-load variations can amplify spanningsval, particularly in a distribution network or electronic systems with sensitive components.

Practical implications include reduced performance of electrical devices, malfunction of sensors, and thermal stress on cables and connectors. Design practices aim to keep voltage drop within prescribed limits, often a few percent of the nominal voltage, by selecting appropriate conductor sizes, shortening runs, improving connections, or using local power supplies and regulation. Measurement typically involves comparing voltage at the source with voltage at the load under expected operating conditions.