ir and cylinder, raising the pressure to the adjustment of the
safety valve.

[Illustration: Fig. 24. Automatic Control Valve. Emergency Position.
(With Quick Action Cylinder Cap.)]

181. Q. At what pressure is the safety valve adjusted?

A. At fifty pounds.

182. Q. What types of brake valve are used with this equipment?

A. The automatic brake valve is of the rotary valve type and is the same
valve as used with the E-T equipment. The straight air brake valve is of
the slide valve type. The control valve takes no part in the application
or release of the straight air brake. What has been said of the H-6
brake valve used with the E-T equipment, applies to the automatic brake
valve used with the L-T equipment.

BROKEN PIPES

183. Q. If the main reservoir supply pipe to the automatic control valve
breaks, what should be done?

A. Plug the pipe toward the main reservoir. The locomotive brake cannot
be applied in an automatic service application; but if the control valve
be equipped with a quick action cap and an emergency application is
made, the air vented from the brake pipe to the brake cylinder will
apply the brake. The independent brake will not be affected.

184. Q. What will be the effect if the release pipe breaks?

A. The holding feature of the brake will be lost; that is, the brake
will release when the automatic brake valve is returned to release or
holding position.

185. Q. If the brake cylinder pipe breaks, can the locomotive brake be
applied with the automatic brake valve? With the independent brake
valve?

A. This depends on where the pipe breaks; if between the cut-out cock
and any one of the brake cylinders, close the cut-out cock to that
cylinder, and the other cylinders may be used. But if the pipe breaks
between the control valve and the double-throw check valve, the
automatic brake is lost; if the break be between the independent brake
valve and double-throw check valve, the independent brake is lost.

186. Q. If the brake cylinder pipe breaks and is not plugged, what must
be done?

A. Close the cut-out cock in the main reservoir supply pipe, this to
avoid the waste of air when a brake application is made on the train.

187. Q. If the brake pipe connection to the control valve breaks, what
should be done?

A. Plug the end leading from the brake pipe; the automatic brake cannot
be applied on the locomotive, but the independent brake will not be
affected.

188. Q. If the c