Ground: labelled reference, IEC style, sheet 1 of 1
Fig. 1
1Earth ground
In the convention used here, three horizontal lines of decreasing length identify a connection to earth. Check a drawing's legend: the same shape is sometimes used more generally for circuit ground.
Fig. 2
1Chassis ground
The chassis symbol (hatched) marks a connection to the equipment's metal frame or enclosure.
Fig. 3
1Signal reference (common)
The signal-reference symbol marks the chosen zero-volt reference for circuit voltages. It need not be connected to earth or chassis.
| Fig. | Terminals | What the terminal is |
|---|---|---|
| 1–3 | 1 | Each ground or reference symbol shown here has one connection point to the circuit; it identifies a reference connection, not a two-terminal component. |
Sources
- Chassis, Earth and Signal Grounding: Terminology and Symbols, NI, retrieved 2026-09-22
- DC Electrical Circuit Analysis — resistive devices and schematic ground symbols (pp. 53, 59–64), James M. Fiore, Mohawk Valley Community College, retrieved 2026-09-22
- Where Is Ground? — local reference versus earth, Analog Devices, retrieved 2026-09-22
- Electrical Schematics, §§1.3.1–1.3.5 — nodes, crossings, references and congruent drawings, Tufts University, retrieved 2026-09-22
- Name
- Class
- Date
- Sheet
- 1 of 1
- Drawing
- Ground Labelled reference
- Style
- IEC style
- From
- circuitsymbols.com
- Licence
- CC BY 4.0