Transcript Introduction to Capacitors - Conestoga Valley Blog Site
Introduction to Capacitors
Electronics 1 CVHS
Terms
Capacitance
- the ability to store energy in the form of an electric charge
Capacitor
- a device designed to hold capacitance
Details Base Unit -
Farad
Typically measured in micro-farads Symbol: F (1/1,000,000th of a Farad) Also can be in pico-Farads (1/1,000,000,000,000) of a Farad Also have a working voltage rating WVDC Similar to resistor power rating Capacitors are not heat sensitive
How a Capacitor Works A capacitor is two conductors (plates) separated by an insulator (dielectric) A capacitor stores energy when it is connected to a voltage source (such as a battery).
Current flows until the capacitor becomes charged to the same voltage as the source.
Simple Capacitor
Discharging a Capacitor Capacitor has the ability to discharge immediately Battery discharges over time Short leads of capacitors before working with them Use a resistor to slowly discharge a capacitor so it is not damaged Danger of Electrical Shock
Factors Affecting Capacitance Plate area Distance between plates Dielectric material
Schematic Symbols Non-electrolytic capacitor Electrolytic capacitor has polarity dielectric soaked in electrolyte Never install backwards Variable capacitor plate surface area can be adjusted
Types of Capacitors Non-electrolytic Ceramic Disc Dipped Mica Paper (molded)
Types of Capacitors Electrolytic Radial Lead Axial Lead
Types of Capacitors Variable
Capacitance Code
NOTE: Value is in pico-farads!
Practice
First Digit Second Digit Third Digit Letter 1 0 4 K 100,000 pF or .1 µF ± 10% 5 2 8 4 2 F 5,800 pF or .0058 µF ± 1% 3 G 24,000 pF or .024 µF ± 2%
Review Capacitance vs. Capacitor Unit of Measure & Ratings How Does it Work?
Working Considerations What affects Capacitance Three Types of Capacitors Capacitance Code