Metering equipment symbols

The following IEC 60417 and ISO 7000 symbols may be used on the metering equipment:

Symbol Reference Title and description
IEC 60417-5017

Earth; ground

To identify an earth (ground) terminal in cases where neither the symbol 5018 nor 5019 is explicitly required.

IEC 60417-5018

Functional earthing; functional grounding (US) *

To identify a functional earthing (grounding) terminal, for example, of a specially designed earthing (grounding) system to avoid causing malfunction of the equipment.

IEC 60417-5019

Protective class I; Protective earth/ground

To identify any terminal which is intended for connection to an external conductor for protection against electric shock in case of a fault, or the terminal of a protective earth (ground) electrode.

IEC 60417-5172

Protective class II equipment **

To identify equipment meeting the safety requirements specified for Class II equipment (double or reinforced insulation).

ISO 7000-0434B

Caution, refer to accompanying documents

To indicate that caution is necessary when operating the device or control close to where the symbol is placed. To indicate that the current situation needs operator awareness or operator action in order to avoid undesirable consequences.

ISO 7000-1641

Operator's manual; operating instructions

To identify the location where the operator's manual is stored or to identify information that relates to the operating instructions. To indicate operating instructions should be considered when operating the device or operating controls close to where the symbol is placed.

* There may be national differences concerning the use of this symbol.

** Protective class equipment requirements are outlined in IEC 61140.