Decelerometer Commercial Vehicle Brake Testing
The following criteria are required for all HGV brake testing.
All brake testing should be carried out away from the sites working area; this should be done in an area that has roughly level ground.
The MOT performance figures are for the Peak Reading:
Service Brake Bare Minimum 50 %
Secondary Brake Bare Minimum 25 %
Parking Brake Bare Minimum 16 %
Although the test requirement looks for a peak reading, you could use the relationship between the peak and average to determine brake performance, if you achieved a peak reading of say 51 – 58 this is not indicating good brakes, peak figures of 70 + can be achieved to indicate good brakes, even though high peaks are recorded if a low average is recorded (20 – 30 example only) this would indicate bad brakes or you will more than likely fail a roller brake test!
Brake Tester Position
The brake tester should be positioned in the foot well of the vehicle, preferably up against a bulkhead with the direction of travel arrow pointing in the intended direction and with the tester straight.
Vehicle Test Procedure
With the vehicle stationary, position and arm the brake tester, accelerate the vehicle at a constant rate in a straight line up to a safe site speed then apply the brakes in an emergency stop manner, hold the vehicle on the brake until the vehicle has come to a complete rest.
Arming The Brake Tester
Turn the Decelerometer BrakeCheck on by pressing and holding MENU until Sbr is displayed on the screen.
Press ENTER, the display will now show the level indicator L-| |-, if this is not the case re-position the BrakeCheck until achieved.
Press ENTER the display should now read 0.00 ± 5. As described above accelerate and brake.
The peak reading will report at the end of the test, if the display still shows L-| |- you did not press ENTER!!
With the Peak reading displayed press ENTER, this will show the average reading. Pressing ENTER again shows further information.
For a Hand Brake Test press MENU twice, this is while the service brake results are displayed; the display should now show Hbr. Now go to the second paragraph under “Arming The Brake Tester” to carry out a test.
For a Secondary Brake Test press MENU three times, this is while the hand brake results are displayed, and the display should now show SEc. Now go to the second paragraph under “Arming The Brake Tester” to carry out a test.
Contact aide automotive to review how a decelerometer is used on a truck or trailer and prices!
Email shoponline@aideautomotive.com
Tel 0115 8456471
