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04) VTEQ brake tester

04.1) VTEQ brake tester theory
04.2) Test procedure
04.3) The results of a brake test
04.4) Optinal pedal force meter
04.5) 4 WD test
04.6) Results review
04.7) Smart electronics

4.3) The results of a brake test

The bar graphs of brake force and brake balance of this front axle have shrunken down to allow space for digital and graphical readouts.

The brake bar graphs indicate the brake force measured just before the wheel(s) looses grip with the roller. This is the measure of maximum brake force. The force is indicated in KN (Kilo Newton).

The balance graph indicates the difference in brake force between left and right during wheel lock up in percents.

The drawn graph indicates the progression of brake force vs. time.
The first part of the graph flat lines low, this is where the brake drag is measured.
The second part of the graph where the brake force flat lines at approx. 1 KN is where the ovality is being checked.
The third part of the graph is where the brake force is increased until lock up occurs.

The digital readouts at the lower part of the screen display (from left to right):

1. The left brake force during lock up in KN.


2. The brake imbalance during lock up.


3. The right brake force during lock up


4. The axle weight in Kg's which is measured on the suspension tester or on the optional brake tester weight sensors.


5. The maximum brake imbalance during any given time on the graph.


6. The axle brake efficiency. The axle efficiency is the result of a calculation that the machine performs with mainly the weight of the two wheels of the axle and the maximum measured brake force of both wheels.

Note:
The axle efficiency indicates instantly if an axle is doing its job slowing the vehicle down. The individual axle effectiveness is not measurable with any 'on road' in vehicle testing devices.

The brake graph can be zoomed for better analyses as this park brake graph illustrates.

The next results screen shows more diagnostic data.

The graph shows in which direction the axle is pulling as a result of the uneven brakes. Again adjustable limits are being used to change display colours. The limits in the graph are indicated by the 4 lines. The green line indicates the brake balance. A perfect brake balance will result in a green line in a 45 degree angle.

The digital readout on the right top of the screen indicates the brake ovality in percent or force (selectable).

On the bottom of the screen are displayed (from left to right):

1. The left residual brake force (drag) in KN


2. The brake imbalance at lock up.


3. The right residual brake force in KN


4. The axle weight


5. The brake imbalance at any given time.


6. The axle brake efficiency.

Continued

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