5
TEBS E
braking system
46
5.9.5 Anti-Lock Braking System (ABS)
Vehicle type
All trailers
Purpose
Prevents locking one or more wheels.
Function
The ABS control logic determines from the wheel rotation speed whether one
wheel or more wheels can be locked and decides whether to decrease, maintain,
or increase the braking pressure on it.
ABS rotational speed sensors
Only the signals from ABS rotational speed sensors c-d and e-f are evaluated for
the ABS control logic.
In all ABS configurations (see chapter 5.4 ‘ABS configurations’, page
) additional
brake cylinders for other axles can be connected to the existing modulators, be-
sides the brake cylinders on the wheels with sensors. These indirectly controlled
wheels do not send any information to the TEBS E. Consequently it is not possible
to guarantee that these wheels will not lock.
Semitrailers, central axle trailers and dolly
The main axle, which is not allowed to be a lifting, steering- or tag axle, always has
the c-d ABS rotational speed sensors. The e-f ABS rotational speed sensors are fit-
ted on the other axle or on the semitrailer axles that can be lifted.
As of TEBS E4 there is exception in the regard for 2-axle central axle
vehicles with 2 lifting axles. Here one or the other lifting axle can be
raised to balance the vehicle in the event of an uneven load. The re-
spectively other axle then becomes the main axle.
Drawbar trailer
The axles with sensors are not allowed to be either a lifting or tag axle with c-d
ABS rotational speed sensors or e-f ABS rotational speed sensors. The c-d ABS
rotational speed sensors must always be put on the modulator side. In this case
the modulator can either be installed at the front, on the drawbar or at the rear.
The status of the lifting axles is read by the ABS control logic. This means that lift-
ing axles with sensors no longer causes speeds to decrease under ABS control. If
the lifting axle is raised, speed information from this axle is not considered when
controlling.
Tire sizes
For optimum function of the ABS control logic it is necessary to parameterise the
installed tire dimensions.
A deviation to the defined tire dimensions of +15 % / -20 % is permissible if this af-
fects all wheels with sensors to the same extent. An individual wheel may only de-
viate from the parameterised tire dimension by a maximum of 6.5 %.
Parameter setting
The tire size is entered via
tab 3
,
Brake data
.