Tilkoblingsstrømmen

Tilkoblingsstrømmen refers to the inrush current that occurs when an electrical device, particularly those with inductive components like transformers or motors, is connected to a power source. This transient current is significantly higher than the device's normal operating current and typically lasts for a very short duration.

The phenomenon arises due to the magnetization of the core material in inductive loads. At the moment of connection, the magnetic flux in the core is usually zero or at a low point. The incoming voltage then tries to establish a magnetic flux, and to do so, it induces a large current to build up the magnetic field rapidly. This initial surge of current can be many times the steady-state current. The exact magnitude and duration of the tilkoblingsstrømmen depend on factors such as the inductance of the device, the point in the AC voltage waveform at which it is switched on, and the resistance of the circuit.

While temporary, tilkoblingsstrømmen can pose challenges. It can cause nuisance tripping of circuit breakers and fuses if they are not rated appropriately to handle these transient surges. In sensitive electronic systems, it can lead to voltage dips on the power supply line, potentially affecting other connected equipment. Therefore, designers and engineers often consider the effects of tilkoblingsstrømmen when selecting protective devices and designing power distribution systems. Strategies to mitigate its impact include using soft starters for motors or specialized current-limiting devices.