411.2 Lighting Systems Operating at 30 Volts or Less. A lighting system consisting of an isolating power supply operating at 30 volts (42.4 volts peak) or less under any load condition, with one or more secondary circuits, each limited to 25 amperes maximum, supplying luminaires (lighting fixtures) and associated equipment identified for the use.
The first question is whether or not the 25A limit applies to a single secondary circuit (e.g. a secondary tap on a low voltage transformer) or whether it can apply to individual wire runs connected to that circuit.
For example, a single secondary circuit tap may be rated by a manufacturer to 30A. Two wire pairs each carrying 15A is connected is to that tap. Would this be a violation?
For now, we'll put aside the question of loading a transformer past 80% of its rating.
The first question is whether or not the 25A limit applies to a single secondary circuit (e.g. a secondary tap on a low voltage transformer) or whether it can apply to individual wire runs connected to that circuit.
For example, a single secondary circuit tap may be rated by a manufacturer to 30A. Two wire pairs each carrying 15A is connected is to that tap. Would this be a violation?
For now, we'll put aside the question of loading a transformer past 80% of its rating.
