49 C.F.R. § 236.206 Battery or power supply with respect to relay; location.
Title 49 - Transportation
The battery or power supply for each signal control relay circuit, where an open-wire circuit or a common return circuit is used, shall be located at the end of the circuit farthest from the relay.
Title 49: Transportation
PART 236—RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND TRAIN CONTROL SYSTEMS, DEVICES, AND APPLIANCES
Subpart B—Automatic Block Signal Systems
Standards
§ 236.206 Battery or power supply with respect to relay; location.
