This Sportbox is travelling around the UK
Acceleration under load
De-acceleration under load
The tests are for noise under load and over the speed range, accelerating and de-accelerating. This means the front end is driven by the rig and the rear end restricted for acceleration, thus loading the transfer box. The reverse procedure is used for de-acceleration. This is the original manufacturers test rig and these graphs accompany every transfer box supplied by Dorfbrunnen as a mark of the final Quality of the workmanship.
If the transfer box has been assembled correctly with the correct pre-stressing and tolerances, then the noises emitted by the transfer box (red line) will be under the acceptable green line. The vertical scale is the noise scale and the horizontal scale is revolutions.