Capacitor Symbols

Capacitor is a two-terminal device characterized essentially by its capacitance.

This article provides a detailed list of capacitor symbols. This list is based on IEC and IEEE standards and contains pictograms and descriptions for the following capacitors: polarized, adjustable or variable, differential, shielded, split-stator, etc.

See also:  relay symbols

SymbolDescriptionNotes
Capacitor, general symbol. Form 1Name: Capacitor, general symbol. Form 1.

Source: IEC 60617-2019, IEEE Std 315-1993
A1
Capacitor, general symbol. Form 2Name: Capacitor, general symbol. Form 2.

Source: IEEE Std 315-1993
A1
Capacitor, polarizedName: Capacitor, polarized. Form 1.

Alternative name: Electrolytic capacitor

Source: IEC 60617-2019, IEEE Std 315-1993
Capacitor, polarized. Form 2Name: Capacitor, polarized. Form 2.

Alternative name: Electrolytic capacitor

Source: IEEE Std 315-1993
Adjustable capacitor symbolName: Capacitor, adjustable

Alternative name: Capacitor with moving element indicated

Source: IEC 60617-2019, IEEE Std 315-1993
A2
Adjustable or variable capacitors with mechanical linkage of unitsName: Adjustable or variable capacitors with mechanical linkage of units

Source: IEEE Std 315-1993
Capacitor, differential symbolName: Capacitor, differential

Alternative name: Continuously adjustable or variable differential capacitor

Source: IEC 60617-2019, IEEE Std 315-1993
Capacitor with pre-set adjustment symbolName: Capacitor with pre-set adjustment

Source: IEC 60617-2019, ANSI/IEEE Std 315A-1986, IEEE Std 315-1993
Capacitor, split and adjustableName: Capacitor, split and adjustable

Source: IEC 60617-2019
Split-stator capacitor symbolName: Split-stator capacitor

Remark: The capacitances of both parts increase or decrease simultaneously

Source: IEEE Std 315-1993
Capacitor, temperature dependent and polarisedName: Capacitor, temperature dependent and polarised

Alternative name: Ceramic capacitor

Source: IEC 60617-2019, ANSI/IEEE Std 315A-1986
A3
Capacitor, voltage dependent and polarisedName: Capacitor, voltage dependent and polarised

Alternative name: Semiconductor capacitor

Source: IEC 60617-2019, ANSI/IEEE Std 315A-1986
A4
Feed-through capacitor symbolName: Capacitor, lead-through

Alternative name: Feed-through capacitor

Source: IEC 60617-2019, ANSI/IEEE Std 315A-1986
A5
Shielded capacitor symbolName: Shielded capacitor

Source: IEEE Std 315-1993
Symbol of phase-shifter capacitorName: Phase-shifter capacitor

Source: IEEE Std 315-1993
Series capacitor and path openName: Series capacitor and path open

Source: IEEE Std 315-1993
A6
Series capacitor and path short-circuitedName: Series capacitor and path short-circuited

Source: IEEE Std 315-1993
A6
Symbol of shunt capacitorName: Shunt capacitor

Source: IEEE Std 315-1993
Coupling capacitor symbolName: Coupling capacitor (for power-line carrier)

Source: IEEE Std 315-1993
A7
Capacitor bushing for circuit breaker or transformerName: Capacitor bushing for circuit breaker or transformer

Source: IEEE Std 315-1993
Capacitor-bushing potential deviceName: Capacitor-bushing potential device

Source: IEEE Std 315-1993
Capacitor with identified electrodeName: Capacitor with identified electrode. Form 1.

Source: IEEE Std 315-1993
A8
Capacitor with identified electrode. Form 2Name: Capacitor with identified electrode. Form 2.

Source: IEEE Std 315-1993
A8

Symbols of capacitors

Application Notes

A1:

In accordance with IEEE Std 315-1993, capacitors may be represented by either of two methods. For convenience in referring to the capacitor symbols in this section, they are classified as follows:

  • Form 1 symbols are drawn with two parallel lines;
  • Form 2 symbols are drawn with one straight and one curved line.

The distance between the plates shall be between one-fifth and one-third of the length of a plate.

A2:

In accordance with IEEE Std 315-1993, if it is desired to indicate the moving element, the common intersection of the moving element with the symbol for variability and the connecting line is marked with a dot. See Adjustable capacitor connecting line is marked with a dot

A3:

Temperature dependent polarized capacitor, where deliberate use is made of the temperature coefficient, for example, ceramic capacitor.

θ may be replaced by to t0.

A4:

Voltage dependent polarized capacitor, where deliberate use is made of the voltage dependent characteristic, for example, semiconductor capacitor.

U may be replaced by V.

A5:

Commonly used for bypassing high-frequency currents to chassis. For purposes of clarity, terminals may be shown on the feed-through element.

A6:

Commonly used on coaxial and wave-guide diagrams.

A7:

The asterisk is not part of the symbol. If specific identifications is desired, the asterisk is to be replaced by one of the following letter combinations:

  • COM – Carrier communication
  • LC – Carrier load control
  • REL – Carrier relaying
  • SUP – Carrier supervisory
  • TLM – Carrier telemetering
  • TT – Carrier transferred trip

A8:

For form 1, if it is necessary to identify the capacitor electrodes, the modified element shall represent the outside or lower potential electrode.

For form 2, if it is necessary to identify the capacitor electrodes, the curved element shall represent:

  • a) The outside electrode in fixed paper-dielectric and ceramic-dielectric capacitors;
  • b) The moving element in adjustable and variable capacitors;
  • c) The low-potential element in feed-through capacitors.

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