SG315

In addition to their numerous uses in circuit protection, Inrush Current Limiters (ICLs) also play an important role in the electrical industry. The SG315 is a trusted ICL from Siemens that is designed to reduce the inrush current associated with power-up in electrical circuits. This article will outline the application field and working principle of the SG315.

Application Field for the SG315

The SG315 is a type of ICL that is often used in industrial applications such as the following:

• Switchgear
• Motor starters
• UPS Systems
• Power Supplies
• Inverters

In these types of applications, the SG315 works to limit inrush current, which can help to prevent system failure caused by localized voltage fluctuations and circuit overload. It is designed to be used in a variety of power supplies, ranging from 277 VAC to 600 VAC.

Working Principle of the SG315

The SG315 consists of a series of resistors, capacitors, and a ferrite core wound with copper wire. When current is switched on, the ferrite core forms a barrier that reduces the amount of inrush current that is able to pass through. Because of this, the current is limited and the power supply remains safe. The SG315 is designed to be placed across the line before the circuit breaker or inrush current-limiting switch.

The SG315 also includes a safety mechanism that functions when an overcurrent is detected. In this scenario, the SG315 triggers a lattice of appropriately sized apertures in the ferrite core, which alters the inductance of the core. This causes an increase in resistance which further limits the amount of current that is able to pass through. The aperture lattice works in a similar way to a fuse but with a much faster response time.

When power is switched off, the ferrite core automatically resets itself and is ready for use when the circuit is powered on again. Because of this, the SG315 is able to provide reliable inrush current limiting time after time.

Conclusion

The SG315 is an essential component for power systems that require reliable inrush current limiting. Thanks to its robust design, it can withstand heavy loads and still provide reliable protection. It is also easy to install and maintain, making it a cost-effective solution for industrial applications.