semiatic

Protective earth (earth in a circle)

Marks the terminal for the protective earth conductor, which protects against electric shock if a fault makes the case live. Equipment that depends on it is Class I (earthed).

Symbol reference: IEC 60417-5019

A mark tells you what the maker declares, never that the product is safe.

What it looks like
The earth sign, a vertical line ending in three horizontal bars that get shorter, drawn inside a circle.
Who may apply it
The equipment maker, on the terminal or screw where the protective earth conductor must connect.

What it does not promise

It shows where the earth must be connected, not that it is connected. The HSE recommends a portable appliance test for Class I equipment so that the earth connection is checked as sound.

Other marks with the same shapes

Sources

Each page below was fetched and read on the date shown. Where a symbol’s IEC 60417 or ISO 7000 number is given, a public page listing that number is among them.

Written in our own words; quotations are the sources’ wording.