Good afternoon; we are designing for a low voltage lighting installation for a multi-story building and are working with a low voltage contractor. We are seeking code interpretation on specifically 411.3 (A) where it mentions that "the output circuits of the power supply shall be rated for 25 amps and 30 volts maximum under all load conditions."
If the contractor is submitting a 48V DC power supply for the class two lighting system, wouldn't this exceed the max voltage of 30 volts?
The really odd part comes in when looking at UL 2108 White Book (Low-Voltage Lighting Systems, Power Units, Luminaires, and Fittings) where in the second paragraph mentions "These luminaires, fittings, controls, and sub-assemblies are rated no more than 30 V ac or 60 V dc. Power units have isoloation between primary and secondary, total output no more than 25 A, and each output limited to no more than 30 V ac or 60 V dc.
Essentially, we'd be out of code if we followed NEC interpretation, but within an NRTL requirement if following UL 2108. The 2014 NEC handbook did not offer any additional information on the subject in regards to the ac/dc interpretation of the 30 Volts.
Any additional clarification would be much appreciated.
If the contractor is submitting a 48V DC power supply for the class two lighting system, wouldn't this exceed the max voltage of 30 volts?
The really odd part comes in when looking at UL 2108 White Book (Low-Voltage Lighting Systems, Power Units, Luminaires, and Fittings) where in the second paragraph mentions "These luminaires, fittings, controls, and sub-assemblies are rated no more than 30 V ac or 60 V dc. Power units have isoloation between primary and secondary, total output no more than 25 A, and each output limited to no more than 30 V ac or 60 V dc.
Essentially, we'd be out of code if we followed NEC interpretation, but within an NRTL requirement if following UL 2108. The 2014 NEC handbook did not offer any additional information on the subject in regards to the ac/dc interpretation of the 30 Volts.
Any additional clarification would be much appreciated.
