Economical ethanol probe
A multidisciplinary, economical and simple PW, which introduces safety at the wheel, the dangers of alcohol on health, metrology (science of measurement), electricity and dilutions.

The ethanol probe (compatible with any data logging system) connects to a standard USB charger (or PC). It generates a voltage that varies according to the concentration of ethanol. Connected to the red led dipole, it lights the LED at the threshold of 0.5mg / l of ethanol, which symbolises the alcohol limit in the exhaled air (to show drunk driving). Connect a multimeter in parallel to show that the voltage generated by the probe increases with the measured alcohol level in the prepared dilutions.