voltage & current sensors
The scope for electrical measurement as obviously as big as the subject itself. Data logging systems tend to measure changes over time and that suits these sensors to measuring the life of a battery, induced emf as a magnet falls through a coil, discharge of a capacitor or surge current when switching on a lamp. There is great learning potential in seeing the way that the current through a bulb, resistor or diode changes as you slide a variable resistor. Likewise use them to see how the current and voltage in a circuit are related (see page 56). These uses are good, but using sensors as simple meters needs to be assessed carefully. It seems wise to look at the economics of replacing inexpensive meters with equipment specially designed for a computer. Otherwise these sensors connect into circuits just as their respective meters do. Check the instructions to see if you need to use a ‘common return’ – this means you connect the return lead of the current sensor to that of the voltage sensor.
My rating **** / +++
I’ve rated these sensors but your assessment will be different. I give * to **** for the sensor’s intrigue, interest, and learning potential. I give from + to ++++ for how often a science department might use it.