Combined device for electrical protection against transient, temporary and permanent overvoltages

摘要

Device provided with a part designed to protect - against transients overvoltages, and another part designed to protect against temporary and permanent overvoltages; the device is associated with electromechanical releases which cause a -switching device to open when there is a supply overvoltage greater than a predetermined period leaving the loads connected downstream of the device without supply, the device is situated downstream of the switching device with which it is associated so that in the event of actuation it is separated from the electrical network, and in addition permits an actuation time which varies according to the level of overvoltage and programmable which prevents unwanted tripping actions, it also processes both the peak and rms values of the network signal and generates a trip signal to the electromechanical releases consisting of a sequence of impulses.