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This page is used to calculate different types of capacitors.

The basic formula to calculate capacitance is: Capacitance=dielectricConstant*area/distance, this formula has good accurancy, as long as the area is large compared to distance*distance.

Most calculations in this program is based on that formula.

- Capacity, used to calculate "charge" and "energy" for known capacitors.
- Area, your must calculate area, can be used for unsupported geometries.
- Square, two stacked square plates.
- Rectangle, two stacked rectangular plates.
- Circle, two stacked circular plates.
- Stack, a number of stacked rectangular plates.
- Roll, a roll with two conductive foils and two isolating foils.
- Tube/coax, two cylinders inside each other
- Sphere an sphere, two spheres inside each other
- Wire, a wire above a groundplane
- Wires, two wires close to each other, i.e. a cable

Capacity | Capacitance of the capacitor to analyze |

Area | Area between plates of a capacitor |

Side | One of the sides in a square |

Width | One of the sides of a rectangle |

Height | The other side of a rectangle of high above a groundplane |

Diameter | Diameter of a circular plate |

Plates | Number of plates stacked |

Length | Length of the foil used for a roll, a coax/tube or a wire |

Conductor thickess | Thickness of the conductor in a roll |

Inner diameter | |

Tube inner diameter | Inner diameter of the large tube in a tube/coax |

Center diameter | Outer diameter of the smaller tube/wire in a tube/coax |

Radius inner sphere | Outer diameter of the smalle sphere |

Radius outher sphere | Inner diameter of the large sphere |

Distance | Distance center of between two wires |

Dielectric | Select the dielectric used or select"User absolute" or "User relative" |

Permittivity | Used when dielectric is "user ...", must be filled with relative or absolute permittivity |

Thickness | Thickess of dielectric |

Applied voltage | Voltage applied to capacitor, used to calculate some electric values for capacitor |

Total area | The total area between the plates |

Capacity | The actual capacitance |

Permittivity (abs)/(rel) | The permittivity of the selected dielectric shown as both absolute and relative value |

Dielectric volume | The volume of the dielectric |

Turns | Number of turns on a roll |

Outer diameter | Outer diameter of a roll |

Field | The electric field in the dielectric |

Charge | The charge on the capacitor |

Energy | The energy in the capacitor |

Energy density | Density of energi en dielectric |

Force | The force the electric field applies to the plates |

- To enter a value in inch, use the calculating ability of the input field. i.e. 3 inch is entered as "3*inch". This constant comes from the Calculator const page (This does NOT work for the wire diameter field, it expects input in mm, not meter)
- Dielectric constant for glass is not included because it can vary between 4 and 15 (relative) depending on glass type

- For calculating serial/parallel connections use Series/Parallel page.
- For calculation charge/discharge curves use Charge curve or Charge time page.
- For calculation impedance of a capacitor use Ohms law page.
- For designing filters with capacitors use 1. order Filters page.