Is there a table showing the ampacities of various sizes of class 2 wiring? Table 402.5 has ampacities for fixture wire (down to 18 gauge). I have run some 16 gauge for some LED lighting but am curious as to whether or not the NEC has a minimum required size for Class 2 lighting systems under 30 volts and what current it can carry. 725.179(H) shows a minimum 18 gauge for class 3 but I can't find anything for class 2. I've seen guys pull 20 gauge stat wire off their trucks for low voltage lights and want to know if that is allowable.