PRONAR T740, Manual, Page: 54 / 136

3.16
FIGURE 3.11 Two conduit pneumatic system diagram with three position
regulator
(1) air tank, (2) control valve, (3) brake force regulator, (4) pneumatic ram, (5), (6) lead
connectors, (7) air filter, (8) air tank control connectors (9) drain valve
Working brake is activated from the tractor driver's cab by pressing on the brake pedal in the
tractor. The function of the control valve (2), applied in pneumatic systems - figure (3.7), is
the operation of the trans-shipment trailer brakes simultaneously when tractor's brakes are
applied Furthermore, in case of an inadvertent disconnection of the conduit between the
trailer and the tractor, the control valve will automatically activate trailer's brakes. Valve used
in the system is equipped with a brake to be applied when trailer is disconnected from the
tractor. When compressed air conduit is connected to a tractor, the device automatically
applying the brakes now changes its position to allow normal brake operation.