92 Ill. Adm. Code 1535.348
Power Source
Section 1535
Section 1535.348 Power
Source
Flashing light signals shall be
provided with two sources of electric operating power, consisting of either two
sources of commercial power, one source of commercial power and battery, or two
batteries. Where flashing light signals, however, are operated by the same
power used for the propulsion of all trains, no additional source of operating
power need be provided.