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7.2.4.5 Luminaires
7.2.4.5.1 A luminaire that is underwater, or within 2,5 m of the water surface,
or so situated that a person has to go into the water to service it, shall be fed
from a transformer that is out of arm's reach from zone 1 and
a) is a class II isolating transformer with a maximum output voltage of
1) 250 V, if the luminaire is used in an ornamental pool or fountain, or
2) 12 V, if the luminaire is used anywhere else, or
b) is an isolating transformer (see 3.83.3) (double-wound transformer)
1) with a maximum output voltage of 12 V, and
2) is protected by an earth leakage protection device that has a rated
earth leakage tripping current (rated residual current) IΔn not exceeding
30 mA.