1. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 1Autumn Quarter AC Electricity Lab 4

2. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 2Autumn Quarter Electric Circuit Components Passive: –Resistors –Capacitors –Inductors Active: –Voltage sources –Current sources –Amplifiers

3. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 3Autumn Quarter Basic Symbols Battery Generator ResistorInductorCapacitor

4. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 4Autumn Quarter AC/DC Comparison

5. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 5Autumn Quarter Simple Circuit: Ohm’s Law V = i * r P = v * i = i2 * r V: voltage (Volts) I: current (Amperes) R: resistance (Ohms) P: power (Watts)

6. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 6Autumn Quarter Basic Power System

7. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 7Autumn Quarter Power System Components Generators Substations: Transformers Transmission Lines Distribution Lines Load

8. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 8Autumn Quarter Generation Energy conversion: Energy balance: MechanicalElectrical InputOutput Losses

9. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 9Autumn Quarter Substations Transformers: –Fundamentals: faraday’s law –Real and ideal –Step-up / step-down –Turn ratio: n –Polarity –Connections: series and parallel

10. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 10Autumn Quarter Ideal Transformer

11. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 11Autumn Quarter Transmission Lines High voltage: –Minimize costs in conductors, towers and equipment –Minimize power loss to increase efficiency –The higher the voltage the smaller the current and therefore the smaller the losses P = V * I

12. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 12Autumn Quarter Connection of Household Appliances

13. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 13Autumn Quarter Power Outlets

14. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 14Autumn Quarter Grounding Provides safety and potential reference

15. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 15Autumn Quarter Hot vs. Cold Resistance Conductors (metals) have resistances that are temperature dependent As heat increases, molecular collisions increase, and resistance to current flow increases as well Thus, as resistive elements get hotter, they become more and more resistive

16. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 16Autumn Quarter Measuring Resistance Cold resistance can be directly measured –Disconnect device under test (DUT) –Attach directly to ohmmeter to take resistance measurement Hot resistance cannot be directly measured –Measure voltage across DUT –Measure current in series with DUT –Ratio of Voltage / Current = Hot Resistance

17. Engineering H191 - Drafting / CAD Gateway Engineering Education Coalition Lab 4P. 17Autumn Quarter Questions ?