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English: Low voltage installations for low voltage devices. Where it's used? For example, in bathrooms or showers. Let's see them:
SELV or safety extra-low voltage - 12V with timer or 24V with overheating protection. In real life you also can see 12V transformers with overload protection in low-voltage halogen lamps.
FELV or functional extra-low voltage - 36V with overload protection and ground wire. During Soviet times it was widely used in filling stations, in Europe it is used in industrial objects with hazards.
PELV or protected extra-low voltage - voltage up to 48V, where one pole is grounded. Overload protection is used only near loads or other line longer than 3 meters.
All of them should have different sockets, which will allow to use devices only with related low voltage system.
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{{Information |Description ={{en|1=Low voltage installations for low voltage devices. Where it's used? For example, in bathrooms or showers. Let's see them: *SELV or safety extra-low voltage - 12V with timer or 24V with overheating protection. In real