How Power is distributed.

Wherever power is required along the route, to operate motors, signals or instruments at stations, intermediate signals or sidings, etc., an overhead line transformer is bridged across two of the power wires and the 3,300 volts pressure between these two phase wires passes through the primary side of the transformer. The secondary side of the transformer draws off (by induction) a portion of current reduced in pressure to 110 volts and transmits this through page 26 wires leading down the pole to the desired point, known as a “location.” These line transformers are so adjusted that the gradual slight drop in voltage (pressure) in the power line, as the distance from the point of intake increases is compensated for; thus the secondary (or low) side of the transformer always supplies current at 110 volts pressure wherever situated on the power line. The work of the main units such as point motors, lever locks, relays, etc., used in operating require current of 110 volts, but certain relay work, track current, signal lighting and diagram lights, etc., require voltages of various pressures (12 volts or lower), supplied by smaller transformers, which reduce the 110 volt supply to any voltage, 12 volts or lower as required.