12
Appendix E – Safety Symbols
12.1 Safety Marking Symbols
This section provides a description of the safety marking symbols that may appear on the instrument. These
symbols provide information about potentially dangerous situations which can result in death, injury, or
damage to the instrument and other components.
Symbol
Publication
Description/Comment
IEC 417, No. 5031
Direct current
.
IEC 417, No. 5032
Alternating current
.
IEC 417, No. 5033
Both
direct and alternating current
IEC 617-2
No. 02-02-06
Three-phase alternating current
IEC 417, No. 5017
Earth (ground) terminal
. Primarily used for functional earth
terminals which are generally associated with test and
measurement circuits. These terminals are not for safety earthing
purposes but provide an earth reference point.
IEC 417, No. 5019
Protective Earthing conductor terminal
. This symbol is
specifically reserved for the protective conductor terminal and no
other. It is placed at the equipment earthing point and is mandatory
for all grounded (Class I) equipment .
IEC 417, No. 5020
Frame or chassis terminal
. Used for points other than protective
conductor and functional earth terminals where there is a
connection to accessible conductive terminals to advise the user of
a chassis connection.
IEC 417, No. 5021
Equipotentiality
Used in applications where it is important to
indicate to the operator that two or more accessible functional
earth terminals or points are equipotential.
IEC 417, No. 5007
On
(Supply)
IEC 417, No. 5008
Off
(Supply)
IEC 417, No. 5172
Class II Equipment protected by double insulation or
reinforced insulation.
The equipment typically does not require a
Safety Ground (Protective Ground).
