13.1.2 Conforming with Block Signals
The cab signal and block signal systems are interconnected so that the cab signal agrees with the block signal indication within 8 seconds after the engine passes the block signal that governs entrance into a block.
The ACS system is to be considered inoperative through turnouts and crossovers. Block signal indications and speeds specified in the special instructions for each turnout govern movements through turnouts and crossovers.
Acknowledging Restrictive Indication
When a cab signal changes to a more restrictive indication, the engineer must acknowledge the change with the acknowledging device. On engines not equipped with the Coded Cab Signal-Safety Control (CCS-SC) System, another member of the crew must
immediately find out from the engineer why the warning whistle sounded longer than 6 seconds. When conditions require, the crew member must stop the train immediately.
On engines equipped with CCS-SC, if the engineer does not acknowledge the more restrictive indication, a full service penalty brake application will occur automatically within 6 to 8 seconds. When this occurs, the engineer must do the following:
When it is known in advance that the ACS system is inoperative in a specific area, crew members will be notified with a track bulletin.
13.1.3 Does Not Indicate Conditions Ahead
Cab signals will not indicate conditions ahead when the engine is:
13.1.4 Cab Signals Cut In and Out
The cab signal on the lead unit must be cut in before entering and while operating within ACS territory and placed in partial cutout after leaving ACS territory.
13.2 Normal Operation
13.2.1 Restrictive to More Favorable
When a cab signal changes from a restrictive to a more favorable indication where a
block or interlocking signal is not located, train speed must not increase until the train moves a distance equal to its length or reaches the next governing block signal, whichever occurs first.
13.2.2 Favorable to More Restrictive
When a cab signal changes to a more restrictive indication, the engineer must comply promptly with the indication received.
13.2.3 Elimination of Audible Indicator
To keep the audible indicator from sounding while the train is stopped in a cab signal test loop, place the reverser handle in either the neutral or reverse position. This will change the cab signal to its most restrictive aspect. After acknowledging the signal change, no more signal changes will be received.
13.3 Unusual Conditions
13.3.1 Cab Signal and Block Signal Do Not Agree
If the cab signal does not display the proper ACS aspect shown in the Block and Interlocking Signal Rules, the engineer must follow the most restrictive block or cab signal indication. The engineer must promptly notify the train dispatcher of the location, signal number, and track where the signals did not agree.13.3.2 Inoperative Cab Signal Device
The ACS system is to be considered inoperative when:
Known in Advance13.3.3 Movement with an Inoperative Cab Signal Device
When it is determined the cab signal device is inoperative, the train may proceed according to block signal indications. However, the train must not exceed 40 MPH until it reaches a point where a crew member can report the defect to the train dispatcher.
When the cab signal device has been cut out, the train must:
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