TESTER & METER > BOWMONK > Automotive > Mechanical BrakeMeter > Tapley Brake Meter


Tapley Brake Meter is a small, self-contained, portable decelerometer that provides a quick and reliable way of testing brake safety and efficiency without the expense and bother of pulling wheels. The same meter can be used to test all types of vehicles, from heavy trucks and buses to vans and passenger cars. It needs no electrical connections and it's so portable that you can take the Tapley Meter to the vehicle instead of the other way around.

Weight-Complete Meters
Each Shipping Quantity**
Metres to Stop
TM 15 Floor Block 10 kg 6 - 70 kg
TM 16 Clamp 2 kg 15 - 30 kg
*All floor Block Mounting Types are supplied with wooden boxes. All other complete meters are supplied in leather carrying cases.
**To optimize packing and freight costs the preferred shipping quantities are as indicated.

TM 15
(Mount Type BrakeMeter)
TM 16
(Clamp Type BrakeMeter)
TM 15 TM 16  

Brake Testing should be carried out on a level road. This can be checked in the case of a strange road by setting the main needle (with arrow) to zero, and then turning the vehicle round so that it faces the opposite direction on the same piece of road. If level, the needle should still return to the zero position. With the main needle at zero, the recording needle should be turned anti-clockwise by means of the chrome knob in the middle of the dial until it is against the right hand side of the main needle. The vehicle is then driven along the level road at about 20 miles per hour, and the brakes fully applied by means of the foot brake pedal only. When the vehicle has stopped the stopping distance result and brake efficiency in %g reading can be taken from the figure shown by the recording needle. The stopping distance figures are the outer numbers shown on the dial face while the %g is the inner numbers on dial. A similar reading should now be taken from a lower speed using the handbrake only. For Department of The Environment testing please follow current regulations from the Department for readings required. For general use the instrument indicates by means of a coloured strip the normally accepted view of brake safety by the Police Force. If the service brake reading is within the red strip zone, then the brakes are definitely unsafe. In the area where the red and green strip is broken the brakes are average or below, and should be considered ready for some kind of attention, and unsafe for fast driving. In the green strip area the brakes are completely satisfactory.

Meter numbers TM 15 and TM 16 has a dial face showing Brake Efficiency of 0-100%G and Stopping Distance in Meters from 3.5 to >60

All Tapley Brake Meters are calibrated to UKAS standards (ISO/IEC 17025:2005) with an uncertainty of measurement of ± 2%g up to 35 degrees of calibration

It is a pendulum-type decelerometer especially designed for convenience of use in motor vehicles on the road. It is accurate and robustly constructed to give long operational life. No special skill is required for its use and reliable results can be obtained with it by following simple instructions.

The meter has only three principal working parts. A heavy pendulum is pivoted at the top so that normally it hangs vertically inside a box which is filled with special oil to damp the movements of the pendulum so that vibration does not affect the indication given. The pendulum is a powerful permanent magnet and when it moves, a light armature follows its movements exactly.

The armature is joined to a toothed segment which in turn drives a pinion to which is connected the circular scale. The scale is read through an opening in the top of the casing and a light ratchet retains the scale at its maximum displacement. The whole mechanism is mounted in a casing carried on pivots which incorporate a fine adjustment so that the casing can be set level before a test. The pivots in turn are mounted on a heavy metal block.