Using multimeters to measure amps and volts
A multimeter - also known as a VOM (Volt-Ohm meter or Volt-Ohm-milliammeter) - is a gizmo for measuring voltage, amperage, and other electronic measurements. Basic multimeters measure volts, amps and resistance, and fancier units have other capabilities. Generally speaking multimeters are used for basic electrical measurements, or finding faults in electrical circuits. When building electric bicycles/motorcycles/cars we need to make many such measurements, be certain we've connected things correctly, and figure out what's gone wrong if the vehicle doesn't work.
The picture to the right is a typical multimeter. The two test leads are touched to electrical circuits, and the control dial is used to determine the measurement which will be taken. On some multimeters, like this one, the dial has to be set to different ranges - for example 0-10 volts, or 0-100 volts, might be two different ranges. Other multimeters are "auto-ranging" meaning you simply select volts or amps and it automatically reads the correct value no matter how much it is.
Some multimeters, like this one, have a digital LED display - and are called Digital Multimeters. Others have a needle showing the readings, and are called Analog Multimeters.
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