BRAKING SYSTEM
TRAILER BRAKING SYSTEM
2.3 TRAILER BRAKING SYSTEM The tractor may be equipped with one of the four following trailer braking systems: 1. hydraulic trailer braking (Italy version) 2. hydraulic trailer braking (Export version) 3. air trailer braking (Italy version) 4. air trailer braking (Export version)
2.3.1 HYDRAULIC TRAILER BRAKING (ITALY VERSION)
Freno a mano Hand brake
1 3 P Y 1
E 2
B
N
2
D0012720
1.
2.
Valve activation lever in position “1” •
When the lever (1) is in position “1” (valve activated) and the brake pedals are not pressed, a pressure of 12.5 bar (181.3 psi) is available at port B.
•
This pressure is supplied constantly to the trailer to release the parking brake.
•
When the operator engages the parking brake, the solenoid valve (2) is energised; this nullifies the pressure at port B.
•
The pressure at port B is directly proportional to the pressure present in the tractor braking circuits Y.
Valve activation lever in position “O” •
10-22
When the lever (1) is in position “O” (valve deactivated), there is no pressure at port B. In this condition, the pressure at port B is always null independently of the pressure in the tractor braking circuits. As a result, the pressure switch (2) detects the lack of pressure and illuminates the indicator light (3) on the dashboard.
