Bosch BSA 250 Betriebsanleitung Seite 41

The system is now ready to start the brake test.
! Drive vehicle slowly onto rollers.
Use the guiding lines (21) on the ground to line up the vehicle.
This ensures that:
– the wheels are positioned approximately in the middle of the
test rollers,
– the vehicle is properly aligned with the rollers,
– the shoulders of the tyres are unimpeded and do not touch the
cover panels.
Select either automatic or manual mode.
Hold the steering wheel firmly when the drive motors are switched
on.
If the vehicle is not positioned at right-angles to the
rollers, it will drift sideways.
Danger to life for anyone standing close to the
roller set!
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In the event of danger, turn the system
kN
off at the main switch.
Turn the steering wheel back and forth to straighten out the
vehicle.
If the front wheels are going to be tested, apply the handbrake.
If the handbrake acts upon the rear wheels, it will prevent the
vehicle from drifting sideways.
i When testing the handbrake, secure the wheels that are not
on the rollers by placing chocks behind them.
Damp brakes distort the test results.
Apply moderate force to the pedal to dry out the brakes.
i You can carry out tests on the SBS and the PBS one after the
other without changing the vehicle position. You must solely
use the remote control to assign the measurements recorded
during the brake test to the correct brake system.
● Testing the SBS (main brakes)
Testing the front axle
Press the button (F6).
This sets up the brake system analyser for measuring the main
brakes on the front axle and transmits the current brake force,
representing the rolling friction, to the computer.
Slowly increase the brake force.
The brake force applied to the wheels at each side is shown on the
LH and RH dials on the control and display unit. If the difference
between the two measured values is greater than 25%, the brake
force difference indicator light (5) illuminates. The threshold value
of 25% has been set up in the factory. A Customer Service
engineer can set the system to a different value, if required.
In order to register out-of-roundness in the brakes, press the
brake pedal until the indicators show approximately half the
maximum brake force (> 500 N).
Keep the brake force constant for 4 s. At the end of this interval, the
process for measuring the out-of-roundness starts automatically.
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While this is taking place, the automatic indicator light (4) flashes.
Continue to maintain the brake force at a constant level while
measurements are performed and do not apply the maximum
brake force until they have been completed. Up to 3 measure-
ments representing out-of-roundness can be registered.
When the maximum slip value is reached, the roller drive motors
switch off automatically. If the brake force is so small during the
test that the automatic slip disable function is not activated, then
Press the S button (F10).
The current measurement is stored by the computer.
The roller drive motors switch off.
The test procedure for the FA main brakes has been completed.
The indicator dials show a reading of 1 kN momentarily to confirm
that the measured values have been assigned to the front axle.
The drive motors switch on again automatically after 4 s.
Drive the front wheels off the rollers.
Drive the rear wheels onto the rollers for testing.
Testing the rear axle
When the drive motors have run up to speed,
Press the button (F7).
This sets up the test bench for measuring the main brakes on the
rear axle and transmits the rolling friction to the computer.
The procedure that follows is the same as for the front axle.
Increase the brake force slowly.
The indicator dials show a reading of 2 kN momentarily to confirm
that the measured values have been assigned to the rear axle.
● Testing the PBS (handbrake acting upon rear axle)
The roller drive motors switch on again automatically after 4 s.
Press the h button (F8).
This assigns the subsequent brake test to the PBS (handbrake).
Slowly increase the brake force applied with the handbrake.
The procedure that follows is the same as for the front axle.
There is no measurement of out-of-roundness during the PBS
test.
The indicator dials show a reading of 3 kN momentarily and the
measured values for the PBS are stored.
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