WABCO 400 500 320 0, Руководство по обслуживанию

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Introduction
3.5 How Trailer ABS Works
WABCO ABS is an electronic system that monitors and controls wheel speed during braking. The system
works with standard air brake systems.
ABS monitors wheel speeds at all times and controls braking during wheel lock situations. The system
improves vehicle stability and control by reducing wheel lock during braking.
The ECU receives and processes signals from the wheel speed sensors. When the ECU detects a wheel
lockup, the unit activates the appropriate modulator valve, and the air pressure is controlled to the wheel
ends.
In the event of a malfunction in the system, the ABS in the affected wheel(s) is disabled; that wheel still has
normal brakes. The other wheels keep the ABS function.
Two ABS indicator lamps (one on the dash of the tractor and one on the side of the trailer) let drivers know
the status of the system.
3.6 System Components
3.6.1 ECU/Valve Assembly (Figure 3.3)
 12 volt for Standard and 8-32 volt for Premium units.
 Integrated ECU and ABS relay valve.
• ECU and valve assembly are serviceable items.
 The ECU/Valve Assembly may be mounted with the control port facing either the front or rear of the
trailer.
Fig. 3.3
2S/2M, 4S/2M STANDARD
2S/2M, 4S/2M AND
4S/3M PREMIUM
2S/1M STANDARD
4015795b
3.6.2 ABS External Modulator Valve (Figure 3.4)
 Controls air pressure to the brake chambers where it is plumbed.

During ABS operation, the valve adjusts air pressure to the brake chambers to control braking and
prevent wheel lock.
 Used in conjunction with ECU/Valve Assembly for 3M systems.