User's Manual

SECTION III OPERATION
SM 7063 07/97 3-27
3.13 EMERGENCY BRAKE APPLICATION
To apply the emergency brakes at the rear of the train, lift up the red switch guard and momentarily
push the Emergency Switch upwards. The switch is spring loaded and will return to the down position
when released. The CDU will immediately transmit an emergency brake command and its
Function
Menu Display
will briefly show
“EMERGENCY BRAKE INITIATED”
.
When the End Unit receives the emergency brake command, it will vent the brake pipe air at the rear
of the train, transmit a confirming message to the CDU, and drop the pressure to 0 psig. As the air
pressure drops, the CDU, in turn, will display a Low Pressure ALARM condition (as described in
Section 3.12.4) and the Brake Pressure Display will show 0 psig.
WARNING
If the Arming Security Feature is enabled in the CDU, the Emergency Switch will
be inoperative until the Arming sequence as described in Section 3.10 is
performed.
CAUTION
The Emergency Switch will activate the Emergency Exhaust Valve of the End
Unit whose ID Code is displayed on the CDU and to which the CDU is Armed.
In the event that the End Unit does not correctly respond to the emergency brake command, the CDU
automatically transmits retries of the command for a period of 2 minutes. The CDU determines a
failure by checking for a brake pipe pressure drop below 5 psig within 4 seconds of the initial
emergency request.
During the 2 minute period, the CDU will indicate one of the following:
1. If the CDU is still receiving updates from the End Unit, the
Function Menu Display
continues to
flash
“EMERGENCY BRAKE INITIATED”
.
2. If the CDU does not receive any updates from the End Unit within 15 seconds, the
Function Menu
Display
will steadily show
“EMERGENCY BRAKE INITIATED”
followed by
a F to R FAILURE
ALARM
(per Section 3.12.3).
At the end of the 2 minute period, the
Function Menu Display
will signal a failure by briefly indicating
“EMERGENCY BRAKE FAILED”
.