The electrical interfaces among the components comprising the auxiliary power systems and their electrical interface with other train-borne systems are described. As such, this standard treats the auxiliary power system components (e.g., static inverters and converters, low-voltage dc power supplies, back-up battery systems, and battery chargers) as black boxes and addresses only their interface requirements.

This standard prescribes the electrical interface between the components comprising the auxiliary power systems and their electrical interface with other train-borne systems. As such this standard treats the auxiliary power system components (static inverters and converters, low voltage dc power supplies, back-up battery systems and battery chargers) as black boxes and address only their interface requirements. It does not provide standards or recommendations for the following: 1) Rotating machinery, such as motor alternator sets 2) Motive power systems or auxiliary power systems required for locomotives 3) Mechanical mounting or vibration isolation of equipment 4) Car-body wiring, branch circuits, circuit breakers and protection devices to interconnect the auxiliary power components with other car-borne equipment.

Standardize the electrical input and output requirements of the auxiliary power system components. This will be conducive to the development of standardized designs rather than custom designs of car-borne equipment utilizing the supply voltages of the auxiliary power systems. It will also aid in more clearly defining the electrical interface requirement between the major component parts comprising the auxiliary power systems, thus promoting their standardized design. The combined effect should increase the number of potential suppliers and correspondingly result in reduced rail car costs.