The Brakemeter / Dynometer is a hand-made precision instrument that mechanically measures both deceleration and acceleration. The instrument consists of a finely balanced pendulum, free to respond to any changes in speed or angle, working through a quadrant gear train to rotate a needle round the dial. The dial is black with silver white graduations and has a linear length of 5 1/2 inches (114 mm). The unit is filled with a special fluid which damps out all vibration. Other than a calibration every 2 years, which is carried out by Bowmonk, no maintenance is necessary.
The dial is calibrated in percentage "G", the accepted standard throughout the world for measuring acceleration and deceleration. There are no connections to the vehicle other than mounting - either with two self-tapping screws onto a heavy stand or by using the suction cup operated by the small side lever.
In the UK, Bowmonk brake meters are approved by the DVSA for use in the annual MOT vehicle-testing scheme. Wherever brake testing is mandatory by law the Bowmonk Brakemeter/Dynometer is an approved brake test instrument. We are a fully approved UKAS testing laboratory and we recalibrate and repair the Brakemeter/Dynometer, the Tapley meter, and our newer electronic decelerometers.