### Single & Three-Phase Power Applications

Overview: Understanding various single and three-phase (poly-phase) power circuits and “why” they are used and “how” to safely connect and measure their electrical properties (line/phase voltages and currents).

• Understanding the role that Resistance, Inductive Reactance, and Capacitive Reactance has in every electrical load and how together they “create” Impedance.
• “Polar” and “Rectangular” numbers will be used to calculate the impedance of electrical loads, voltage drops, and the amount of current being drawn by different load types.
• Understanding true power (watts), reactive power (volt-amps reactive), and apparent power (volt-amps) and their roles in the power system.
• Explanation of the term “Power Factor” and why a “good” Power Factor is so important in maintaining the life of electrical equipment and how to avoid additional costs associated with the “Power Factor Penalty”. The concept of a “leading” and “lagging” Power Factor will be thoroughly understood.
• How to properly size a capacitor-bank in “KVAR” to achieve unity power factor.
• How to properly size a transformer in “KVA” in conjunction with the load(s) being served.
• Each employee will calculate the phase /line voltages and currents of a 480v/277v and 208/120v, three-phase distribution system. An explanation of the “split delta” (high-leg), three-phase configuration and why it could be dangerous if misunderstood.
• A discussion of transformer types, construction, operation, and maintenance will be presented. The transformer “turns-ratio” will be applied to find the primary/secondary voltages and currents. The relationship between line and phase voltages and currents will be explained with respect to three-phase delta and wye configurations. Harmonics will be defined and understood.

NOTE: Hands-on labs will demonstrate how to safely connect and measure the voltage and current for single-phase power configurations and the line/phase voltages and currents for various three-phase power configurations.