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).
Since liquids exert force equally in all directions we can multiply the force it gives by increasing the surface area in which we want the liquid to push against. Typically we apply this principle in a hydraulic cylinder. The greater the surface area at the end of the cylinder, the more force gets exerted on the moving piston.
A circuit is a closed loop of wiring and components beginning at the positive side of the battery and ending back at the negative side of the battery. This loop is often closed using a common ground. Electricity only flows when a circuit is a closed loop. If the loop is open no electricity flows.
This can be illustrated with this math formula: Force = Pressure x Area.So if we were to push liquid at 1,000 psi into a cylinder with an end area of 2 square inches we would produce 2,000 pounds of force. If we were to enlarge the end area by using a larger diameter hydraulic cylinder with a 4 square inch end area, we would produce 4,000 pounds of force. Since the displacement of the larger cylinder will be greater, our cylinder will move slower but with greater force. Like all other forms of mechanical advantage, we trade speed for power.