General Order 64-A
Detailed Construction Requirements For Trolley Lines
(Class T Circuits)
74.3 Material and Strength (See Sec. IV, Rule 49.4)
In determining strength requirements, Class T lines are classed as ordinary supply lines of equal voltage and will take grades of construction accordingly. This will generally mean Grade “C” construction for D.C. trolley lines of 0-750 volts, Grade “A” or “B” being required at crossings over railways according to the importance of the railway crossed.
The minimum size which shall be used for trolley contact conductors on public streets or highways is No. 0 solid copper, or other wire of equal strength.
The minimum size of wire to be used as a feeder span or feeder auxiliary span wire shall be No. 4/0 stranded copper. Other Class T conductors shall comply with Rule 49.4 and 54.