International Electrical Symbols; Definition Of Measurement Categories - AEMC 670 User Manual

1.1

International Electrical Symbols

This symbol signifies that the instrument is protected by
double or reinforced insulation.
This symbol on the instrument indicates a WARNING and that
the operator must refer to the user manual for instructions
before operating the instrument. In this manual, the symbol
preceding instructions indicates that if the instructions are not
followed, bodily injury, installation/sample and product damage
may result.
Risk of electric shock. The voltage at the parts marked with this
symbol may be dangerous.
This symbol refers to a type A current sensor. This symbol sig-
nifies that application around and removal from HAZARDOUS
LIVE conductors is permitted.
Ground.
In conformity with WEEE 2002/96/EC.
1.2

Definition of Measurement Categories

CAT II: For measurements performed on circuits directly
connected to the electrical distribution system.
Examples are measurements on household
appliances or portable tools.
CAT III: For measurements performed in the building
installation at the distribution level such as on
hardwired equipment in fixed installation and
circuit breakers.
CAT IV: For measurements performed at the primary
electrical supply (<1000V) such as on primary
overcurrent protection devices, ripple control
units, or meters.
4
Clamp-on Meter Models 670 and 675