Think of voltage as electrical pressure; amperage as the volume of electricity flowing; and resistance as electrical friction that resists current. Direct Current or DC is electricity flowing from a battery. Alternating Current is electricity flowing from an alternating power source such as a stator.
The ability to detect, observe, and measure electricity is crucial when trying to understand how a tractor works and learning what you can do to fix it. The digital multi-meter is like a doctor’s stethoscope. It allows us to see the invisible force of electricity and measure how it interacts with the components in our engines and tractors. A digital multi-meter measures current (amps), voltage (volts), and resistance (ohms).