Epcos – Active Components

Epcos are one of the worlds leading suppliers of passive components offering products such as capacitors (aluminium, film, power & PFC), Ferrites & accessories, Wound components, EMC filters, Varistors & thermistors.

An EPCOS gas-filled surge arrester, which consists of a stack of five individual arresters, offers reliable quenching of an applied dc voltage. It has a rated dc operating voltage of 48 V dc plus 20%, according to IEC 61643-11. Surge current capability measures 20 kA at an impulse wave of 8/20 µs, and 4 kA at an impulse wave of 10/350 µs. The arrester, developed by TDK Corp., corresponds to a climate category of 40/90/21 of IEC 600068-1, and operates from -40 to +90°C. Thanks to a capacitance of less than 1 pF (1 MHz) and insulation resistance of more than 10 GΩ (100 V dc), the RoHS-compatible surface-mount component has negligible parasitic coefficients. It’s specifically designed to protect dc power supplies in telecom equipment. Size is 1.6 by 8.4 by 8.9 mm3.

Epcos' Surge suppressors or surge arrestors are designed to protect electrical devices from voltage spikes, surges, or transients in the power supply. These events can be caused by lightning strikes, power grid fluctuations, or other electrical disturbances.	World’s smallest arrester: Epcos Surge arresters, also known as lightning arresters or surge protectors, are devices designed to protect electrical systems from voltage spikes or surges. Surge arresters work by diverting excess voltage to the ground, thereby preventing damage to sensitive electronic equipment.	Electrode Arresters: Surge arresters are GDT (gas discharge tube) voltage protection devices. Epcos TDK offers a strong lineup of products with a variety of surge current capabilities ranging from lightning protection for power lines to lightning protection for signal lines.
	Surge Arresters LN8 Series of Stacked Surge Arresters for Telecommunications Equipment	Arrester stack for telecommunications equipment

Gas-filled surge arresters operate on the principle of an arc discharge. Electrically, they act as voltage-dependent switches. As soon as the voltage applied to the arrester exceeds the spark-over voltage, an arc is formed within the hermetically sealed discharge chamber in a matter of nanoseconds. The arc forms a short circuit over which the entire current flows, instantaneously eliminating the overvoltage. When the discharge has dissipated, the arrester extinguishes and the internal resistance immediately returns to values of several 100 Mohms. In this way surge arresters almost perfectly fulfill all requirements made on a protection element. They reliably limit the overvoltage to permissible levels, and – under normal operating conditions – their high insulation resistance and the low capacitance mean that there is virtually no impact on the system to be protected.

Sample application:

• Telecom Applications
• Surge protection device (SPD) for power supplies
• Protection circuit for solar power conditioners generation systems
• Overvoltage protection of Ethernet interfaces