Phoenix Contact, PT-BE/FM Surge Suppressor Unit 240 V Maximum Voltage Rating Base Element

MAINS-PLUGTRAB is a slim design surge protector designed to protect the low voltage single-phase power supply of very sensitive equipment.
It quenches over voltage as a result of inductive or capacitive connections.
Its pluggable design allows for easy maintenance (surge protector plug combined with a base for electrical connection). Disconnection feature provides continuity of electrical power supply.
Features a mechanical indicator which provides a status (operational or out of order) at all times and changeover contacts for alarm reports.
Connects in series directly upstream of the device that will be protected, and is mounted on a symmetric profile.

Voltage surges, often referred to as spikes or transients are typically caused by switching of fluorescent lights, fuses blowing or nearby lightning activity. The worst voltage spikes are usually caused by lightning strikes and can reach up to 6000V, with current surges of over 3000A. The maximum size of the let-through voltage and current inrush depends on the location within the building's wiring system. BS7671: 2011 Amendment 1 Sections 443 and 534 cover risk assessment and provides guidance on protection of electronic equipment for installation engineers to follow. The fullest information on lightning and surge protection comes from the BSEN 62305 series of standards.