Digital Multi-Meters come in two common varieties: Auto- Ranging, and Non Auto-Ranging. A non auto-ranging meter requires you to select a range of “sensitivity” for the given function you are using. For example if you want to measure resistance, you would need to select a range of up to 200 ohms, up to 20Kohms (20,000 ohms), 200Kohms, etc. An auto-ranging meter will automatically figure out the range and give you a measurement.
The reservoir holds the fluid; in the case of our garden tractors, oil. The pump moves oil throughout the entire system. The valve directs oil to different hydraulic cylinders or motors. The Piston or Motor is where the final work is performed. A piston will move loads up and down, and a motor will rotate. All of the components are connected by hydraulic hoses or lines.