Count / Tachometer Adaptor

datalogging sensors


Data Harvest

Product Description

Counts electrical pulses and presents the data as either a number of events or a rate value. 

11 ranges to select. The adapter has two inputs, one for SmartQ digital sensors (light gates, push switches),and the other for simple switches (user created) terminating in a 3.5mm jack plug.

Count up to 60,000 cumulative events or the speed of a rotating bicycle wheel. Investigate Newtons’s laws with Atwood’s machine or count red and green buses, anything where you count an event or use events per unit time for rate e.g. revs/second, miles per hour, rpm, counts /second. 


Teaching applications:
  • Measure the distance and speed of a road bicycle
  • Record wind speed
  • Get distance measurements from a spoked pully
  • Study circular motion
  • Tally counting

Extensions and advanced ideas:
  • Make an Atwood’s machine and measure g (Newton's second law)
  • Link to a dynamics cart and measure time, distance, speed, acceleration
  • Use as single event trigger for other sensors
  • Count monitoring of events e.g. number of times a door is opened
  • Connect SmartQ digital sensors to the din socket e.g. Light gate, push button switches.
  • Connect ‘push to make’ switches to the 3.5mm socket.
  • Push button to reset data to zero.
  • Indicator LED shows a pulse has been counted.
  • Measure circumference of any wheel to record distance, use software to produce speed and acceleration.
  • Switch bounce limiting circuitry.



Cumulative: 0 to 1,000, 0 to 60,000, Counts/second
Revs: per minute, per second
Wind Speed (Anemometer): m/s, mph
Rain fall (Rain gauge): mm
Speed (Spoked pulley): m/s, mph
Distance (Spoked pulley): m 


Download Count Tachometer Sensor Manual  Doc No.: DS104 | Issue: 2




Atwood's Machine Newtons second law (Physics (14-18) Motion & Forces eBook)
Atwood’s machine provides a simple and economical way of testing Newton’s 2nd Law. It is two masses hanging either side of a free running pulley. The accelerating force is the difference between the weights of the two masses.




How fast Is the wind speed (Science in Sport (11-18) eBook)
In this investigation you will be asked to create a simple cup anemometer and record wind speed. If the air is very still you may need to use a desk fan. The results from your device can then be compared to the results from a calibrated “gold standard” Wind speeds are critical for record performances.

HK$ 550.00