CL-70

Inrush Current Limiters (ICLs) are a specialized form of electrical component that is used to protect against the overloading of electrical systems due to sudden high surge currents. CL-70 is a type of ICL that serves as a high power current limit circuit that is mainly used to protect semiconductor devices, power stages and electronic systems from the potentially hazardous effects of transient inrush currents. The basic hardware of a CL-70 system consists of two resistors, an N-Channel MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), and a capacitor. The two resistors act in series to limit the inrush current, while the MOSFET helps to limit the voltage applied to the components. The capacitor is used to store charge for later use.

The primary function of a CL-70 is to limit the amount of inrush current drawn by a load, often during the power-on startup. This prevents the motor from drawing too much current, which could damage components and possibly lead to the failure of the entire system. Additionally, it reduces the amount of energy required to power the load, which may lead to an increase in power savings. The CL-70 circuit also serves as a form of surge protection, as it limits the voltage applied to the load, and prevents it from exceeding safe levels.

The primary application of CL-70 in industrial automation is in the protection of circuits from inrush current transients, such as power supply inrush or switching transients. In addition, it can be used to provide additional protection for devices such as drivers, servo motors, and power supplies. CL-70 can also be used in domestic applications to protect electronics and small motor circuits from damage due to inrush current transients.

The working principle of the CL-70 is simple. When power is first applied to a load, a momentary reverse voltage is applied. This reverse voltage causes a brief surge of inrush current, which is much higher than the normal running current. The two resistors in the CL-70 circuit limit the current flowing through the load, thus preventing any damage resulting from the inrush current. When the inrush current stops, the voltage across the resistors and the MOSFET is reduced and the current begins to flow in the normal direction. The capacitor stored charge helps to reduce the voltage applied, and ensures that the current flows in the correct direction.

The CL-70 current limit circuit is an effective and reliable way to protect electrical components and systems against the damaging effects of transient currents. This type of current limit circuit is easy to install, and requires minimal maintenance. It is suitable for a range of applications, from industrial automation to domestic use.