ST Series, Inrush Current Limiters (ICL)

Inrush Current Limiters (ICLs) are components designed to control and limit the initial surge of electric current that occurs when an electrical device is switched on. This surge, known as inrush current, can be significantly higher than the steady-state current required for normal operation. The primary function of ICLs is to protect the electrical circuit and its components from damage caused by the high inrush current. This surge can potentially overload sensitive devices such as power supplies, transformers, and motors, leading to malfunctions or even component failure. By limiting the inrush current, ICLs help ensure the safe and reliable operation of the devices they are installed in. ICLs achieve this by providing a controlled path for the initial surge of current to flow through. They have a specific resistance that regulates the flow of current during the startup phase of the device. This resistance gradually decreases as the current stabilizes, allowing normal operation to continue without any impedance. The specifications of ICLs can vary depending on the application. The steady-state maximum range of current that ICLs can handle typically falls within the range of 100 milliamperes (mA) to 80 Amperes (A). The resistance at current can range from 1 milliohm to 30.3 ohms. Additionally, ICLs come with different lead spacing options, ranging from 0.098 inches to 1.378 inches, to accommodate various circuit designs. Ultimately, Inrush Current Limiters play a critical role in circuit protection by mitigating the risk of overload and damage caused by inrush current. Their ability to control and limit the surge helps ensure the longevity and reliability of electrical devices and systems.