141. What capacity allows for additional services in a 480 V system?
142. A 500 Amp residential power system requires what size of a grounding electric conductor?
143. Interior metal piping can be used for a grounding electrode if it is connected to within how many feet after entering the building?
144. Equipment grounding conductors shall be identified as?
145. The edge of a bored hole through a 2X4 wall member has to be how far from its edge if a plate is not used?
146. Direct buried conductors are required to have an enclosure protecting the wire extending a maximum of how far down and how far up?
147. A 250 Amp service cable for a dwelling is required to be what size?
148. A UF conductor delivering 20 amps is required to be what size?
149. What is the minimum size copper conductor allowed for branch lines?
150. What type of service entrance cable is identified for underground use?