EET Survey of Electronics Chap Circuit protection devices Chap Electric Power

Undesirable Circuit Cond. Overloads - excessive current for wire size. –Ampacity determined by size of wires used Short Circuits –Special case of Overloads - 0 load resistance Ohms law says I = V/R = V/0 =

Fuse and Circuit Breakers Rated in amps Fuse consists of link that melts at a rated current - opening circuit Breaker heats a bi-metal strip that opens circuit mechanically

Fuse Packages Dependent on application

Testing Fuses Using a continuity tester Ohmmeter –Good fuse tests ~ 0 ohms –Blown fuse = infinity (OL) To replace fuses – use fuse puller

Circuit Breaker operation

Other Circuit protections Thermal Overload Protection –Motors, computer power supplies Lightening Rods/Arresters –Surge Suppression Power conditioning –Eliminate RF noise –Produce sinusoidal voltage

Chapter 19 - Electric Power Electrical Generation –Hydroelectric –Thermal Electric Coalstrip

Nuclear Power

Alternative Generation Wind power Solar Power –Photo-voltaic cells Magneto Hydrodynamics –Use plasma as part of generation current flow

Fuel Cell Converts hydrogen directly to electricity Ballard Fuel Cell –Uses PEM technology Proton Exchange Membrane (PEM) Fuel Cells

Power Transmission Distribution to from the generation facility to the customer. Sequence of step-up / step-down transformation

Calculating power –P = V x I I 2 R

Look at the Internet for examples of alternate power generation –Alternative generation equipment –Alternative fuels Chapter 19: 1-10 Read Chapter