OVR type 1 + 2 is designed to discharge high current surges without any destruction of the installation. This surge protective device is chararcterized by its capacity to withstand impulse current with 10/350 µs wave form which simulate direct impact coming from a natural lightning current. Type 1-type 2 SPDs are placed at the entrance point of the installation, in the main distribution board for a global protection of this installation. · Din ¡El impulse current of 25kA per pole (10/350 µs wave) satisfies all requirements for overvoltage surge protection · ¡El early creation of the electric arc by its electronic ignition device reduces the protection level Up to an optimum value of 1,5kV · OVR T1+2 SPDs contain a dedicated arc chamber for extinguishing the electrical arc following the discharge, they can open short circuits.