# Socket outlet with protective earth contact Canonical URL: https://eloragrid.ai/symbols/iec-socket-outlet-with-protective-contact Publisher: Elora Grid Updated: 2026-10-28 Lookup label: SO Drawing use: GA Reference families: IEC ## Symbol convention Convention: IEC Form: Socket outlet with protective contact IEC 60617 installation-plan style (architectural and topographical installation symbols); independently drawn, not certified IEC geometry or a database identifier. Related representation: [Single power receptacle](https://eloragrid.ai/symbols/iec-single-power-receptacle) Installation plan mark for a socket outlet that includes a protective earth contact for Class I appliances. ## In plain English ### What does Socket outlet with protective earth contact mean? On an installation plan this mark places a socket outlet whose contact set includes a protective earth pin or earthing clip. The basic half-circle outlet form is completed by a straight bar across the top of the curve, which tells the reader that the outlet connects the protective conductor of the final circuit to the plug. ### A simple example Most general-purpose outlets in Australian, British and European buildings are earthed, so many project legends use this form as the default outlet. Where a legend shows both earthed and unearthed outlets, the bar is the only visual difference and should be checked carefully at shaver points, double-insulated equipment locations and extra-low-voltage outlets. ### What the drawings help you do The mark does not state the plug pattern, current rating, mounting height or circuit number. Those come from the legend, outlet schedule and circuit labels written beside the symbol. ### This particular reference Installation plan mark for a socket outlet that includes a protective earth contact for Class I appliances. A plain socket-outlet mark shows an outlet position only; the earth bar adds the protective contact. The protective earth terminal symbol itself is a schematic conductor mark, not an outlet. ### Terms - Normally open / normally closed: The contact state in the normal condition defined for the drawing. - Rating: A value stating the conditions for which equipment is specified. - Schematic: A drawing showing function and connections rather than physical appearance. Concept diagram: Identify the device and form → Read the connections and state → Check the equipment reference A guide to reading this reference. The original symbol illustration and its drawing notes appear below; these boxes are not a wiring diagram. - [IEC graphical symbols for diagrams](https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/) - [Autodesk IEC-60617 preview: Single and duplex power-receptacle forms](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-7DAEDB03-74FC-47A2-9C50-9164297AA5A3.htm) - [Electrical installation design methodology and references](https://www.electrical-installation.org/enwiki/General_rules_of_electrical_installation_design) ## What it represents On an installation plan this mark places a socket outlet whose contact set includes a protective earth pin or earthing clip. The basic half-circle outlet form is completed by a straight bar across the top of the curve, which tells the reader that the outlet connects the protective conductor of the final circuit to the plug. Most general-purpose outlets in Australian, British and European buildings are earthed, so many project legends use this form as the default outlet. Where a legend shows both earthed and unearthed outlets, the bar is the only visual difference and should be checked carefully at shaver points, double-insulated equipment locations and extra-low-voltage outlets. The mark does not state the plug pattern, current rating, mounting height or circuit number. Those come from the legend, outlet schedule and circuit labels written beside the symbol. ## How to read it - Look for the bar above the half circle; without it the outlet may be unearthed or simply drawn in a simplified style. - Read the circuit tag next to the symbol to find which final subcircuit and protective device feeds it. ## Information to show or reference - Confirm the plug standard and current rating in the outlet schedule. - Tag each outlet with its distribution board and circuit number. - State mounting height or reference a typical mounting detail. ## Important distinction A plain socket-outlet mark shows an outlet position only; the earth bar adds the protective contact. The protective earth terminal symbol itself is a schematic conductor mark, not an outlet. ## Facts - Drawing role: Outlet position on a floor plan - Added information: Protective earth contact present - Exact standard graphic: Not reproduced here; confirm the form against IEC 60617 and the project legend ## Public references - [IEC graphical symbols for diagrams](https://tc3.iec.ch/tc-activity/graphical-symbols-for-diagrams/) — IEC. IEC committee context for graphical symbols used in diagrams and installation documents; not a source of reproduced artwork. - [Autodesk IEC-60617 preview: Single and duplex power-receptacle forms](https://help.autodesk.com/cloudhelp/2021/ENU/AutoCAD-Electrical/files/GUID-7DAEDB03-74FC-47A2-9C50-9164297AA5A3.htm) — Autodesk. Public receptacle family in an IEC-oriented CAD library, useful for comparing schematic receptacle forms with plan marks. - [Electrical installation design methodology and references](https://www.electrical-installation.org/enwiki/General_rules_of_electrical_installation_design) — Schneider Electric — Electrical Installation Guide. Installation design methodology context: circuits, outlets and final distribution are planned before symbols are placed. ## Graphic scope Independent original educational concept illustration by Elora Grid. Not a certified standards graphic or manufacturer footprint. Unitless; not to scale. Original artwork licence: https://creativecommons.org/licenses/by/4.0/. Publisher material is linked only.