Phoenix Contact, PT 2X1-24DC/FM-ST Surge Protector 20 V ac, 28 V dc Maximum Voltage Rating 20kA Maximum Surge Current

PLUGTRAB PT-IQ intelligent and systematic surge protection system for measurement and control (MCR) technology. It is the first solution to offer direct early detection of damaged surge protective devices using a three-stage status display to indicate the state of the protective device/s. (Green - OK; Yellow - Performance limit reached and replacement recommended; Red - Overloaded and replacement required)

The design of the rugged PLUGTRAB PT-IQ surge protection module system is such that
it is not possible to incorrectly connect each module, it is easily extended with each controller monitoring and supplying up to 28 protective devices and each module locks securely in place it makes this system particularly suited to provide reliable protection in tough conditions.

Key features of the system are:-

Unique three stage indication system flags damaged as well as failed plugs
Energy efficient as the Green indicator can be turned off by the control unit
Suited for use in demanding environments
Incorrect connection is not possible due to voltage keying and protection against polarity reversal, ensuring error free installation
Space saving design as one device protects up to five signal lines
Conventional wiring is not required as power supply and status information is communicated by converting the individual DIN rail connections into a bus
Contact with DIN Rail is such that it is resistant to surge currents
DIN rail system controller can accommodate the monitoring and supply of up to 28 protective devices
Direct or indirect grounding connection options available to cover a wide range of applications

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.