Protectors against permanent overvoltages act by disconnecting the receiving facilities from the power supply network that suffers the overvoltage, thus protecting the installations against its effects.
Permanent or temporary overvoltages are increases in potential of over 10 % of the nominal value of the power supply, which remain for several cycles or even permanently.
They are a result of phase decompensation, which is usually caused by the neutral conductor breaking, its faulty connection or faults in transformer centres.
What damage can the permanent overvoltages cause?
Permanent overvoltages concerns mainly the power supply. The long duration of the overvoltage may cause the loss of service to electric and electronic connected equipment. This elevated voltage affects also the devices decreasing their service life and overheating them until causing irreparable damage or even fire.
Internationally, the application standard is EN IEC 63052:2022 “Power frequency overvoltage protective devices (POPs) for household and similar applications”.
Our Permanent Overvoltages Protective Devices range
This overvoltage guide is published to achieve a correct protection of any installation by choosing, just with a few questions, the proper Permanent Overvoltages Protective Device model.
Main protective device included?
Self-reclosing / Non self-reclosing?
Single- or Three-phase line?
Manual reclosing protection
Disconnection from the power supply network by means of a mains protection device. This device could be a main circuit breaker or a residual current device and must include a shunt release. Reclosing is done manually.
Protection + main protective device
Protectors against power frequency overvoltages with manual reclosing + main protective device.
Disconnection from the power supply network by means of a self-reclosing device. This device could be a contactor and is very useful in second residences, public lighting and, generally speaking, in non-assisted areas.
Protection + protective device
Protectors against power frequency overvoltages with automatic reclosing + protective device.