Sparkfun Capacitor Kit : $7.95

Digikey 10000uF (0.01F) capacitor $3 each

The energy stored in a capacitor is electrostatic potential energy and is thus related to the charge Q and voltage V between the capacitor plates. A charged capacitor stores energy in the electrical field between its plates.

Capacitance: the ability of a system to store an electric charge. The ratio of the change in an electric charge in a system to the corresponding change in its electric potential.

Capacitor: a device used to store an electric charge, consisting of one or more pairs of conductors separated by an insulator.

Coulomb: the SI unit of electric charge, equal to the quantity of electricity conveyed in one second by a current of one ampere. The coulomb (symbol: C) is the International System of Units (SI) unit of electric charge. Under the 2019 redefinition of the SI base units, which took effect on 20 May 2019, the coulomb is exactly 1/(1.602176634×10 ) elementary charges. The same number of electrons has the same magnitude but opposite sign of charge, that is, a charge of −1 C.

Farad: the SI unit of electrical capacitance, equal to the capacitance of a capacitor in which one coulomb of charge causes a potential difference of one volt.

1 Farad = 1000mF = 1 million uF = 1 billion nF = 1 trillion pF

m = milli

u = micro

n = nano

p = pico

2 digit markings mean pF: 22 = 22 pF

3 digit marking: 104 = 1 and 0 is 10. 4 represents 10^4 so 10 x 10^4 or 100,000pF = 104: 100,000 pF = 100nF

Ceramic | |||

Marking | pF | nF | uF |

10 | 10 | 0.01 | |

22 | 22 | 0.022 | |

101 | 100 | 0.1 | |

102 | 1000 | 1 | |

103 | 10000 | 10 | 0.01 |

104 | 100000 | 100 | 0.1 |

Let’s look at what a Farad and Ampere-Hour is?

1 F = 1 As/V

1Ah = 3600As

Maintain 1Ah @ 12V you would need?

3600As/12V= 300F

EIA Tolerance Capacitor Marking Code | |
---|---|

Letter code | Tolerance |

Z | +80%, -20% – this is used with electrolytic capacitors where the minimum value is the major issue. |

M | ±20% |

K | ±10% |

J | ±5% |

G | ±2% |

F | ±1% |

D | ±0.5% |

C | ±0.25% |

B | ±0.1% |

EIA Capacitor Voltage Codes | ||
---|---|---|

0G = 4.0VDC | 1J = 63VDC | 2D = 200VDC * |

0L = 5.5VDC | 0k = 80VDC | 2P = 220VDC |

0J= 6.3VDC * | 2A = 100VDC * | 2E = 250VDC * |

1A = 10VDC * | 2Q = 110VDC | 2F = 315VDC |

1C = 16VDC * | 2B = 125VDC | 2V = 350VDC |

1E = 25VDC * | 2C = 160VDC | 2G + 400VDC * |

1H = 50VDC * | 2Z = 180VDC | 2W = 240VDC |