the control reservoir dissipation check valve in which case
only one application and release will be required to reduce
an over-charge.
2.1.3 GRADUATED & DIRECT RELEASE
2.1.3.1 A Graduated or Direct Release function can be
obtained with the “26-C” Control Valve, depending upon the
manual positioning of the release cap. For Graduated Release,
the cap on the Control Valve is set in “GRA” position.
Air will be permitted to flow from the control reservoir through
choke H and into Passage 9a, and Choke G which leads to
the selector volume reservoir. However, if the cap is positioned
for Direct Release, the flow of air from the control
reservoir is directed to not only the selector volume, as previously
described, but may now also flow from Passage 7a
to 1-b in the release cap that leads to the control reservoir
dissipation check valve and Choke J and into brake pipe.
(Proper positioning of the cap is dependent on the “make
up” of the train consist).
IMPORTANT: Graduated Release is NOT to be used on
train consists which exceed 24 cars. Total length of consist
MUST BE less than 2160 feet (24-ninety foot cars).
2.1.4 EMERGENCY
2.1.4.1 During and Emergency Brake Application, the
“26-C” Control Valve functions similarly to that previously
described; however, several additional features designed
into the Control Valve are utilized as follows:
2.1.4.1.1 An Emergency reservoir is not required with the
“26-C” Control Valve. The auxiliary (supply) or main reservoir
is utilized to obtain the higher braking pressures desired
during emergency applications.
2.1.4.1.2 The increased pressure differential across the
diaphragm in the selector valve, as a result of the faster rate
of drop in brake pipe pressure, positions the diaphragm
assembly and spool to provide those functions obtained during
a service application.
2.1.4.1.3 The upward movement of the service valve unseats
the application valve to permit auxiliary (supply) or
main reservoir air to flow to the brake cylinder limiting valves
and into Passage 16 which is connected to the brake cylinder
application pipe or brake cylinder relay valve control
pipe.
2.1.4.1.3.1 Auxiliary (supply) or main reservoir air flows to
the underside of the service limiting valve spool. Whenever
this pressure reaches a point in slight excess of the spring