User manual

User Manual Compliance Test System 3.0
11.3 Equipment Classifications
In Annex B of the standard, the EUT operating environment classifications are defined based on
IEC 61000-2-4. The classifications are as follows:
Class 1
Applies to protected supplies with compatibility levels lower than public network
levels. It relates to the use of equipment, which is very sensitive to disturbances
in the power supply, for instance the instrumentation of technological
laboratories, some automation and protection equipment, some computers etc.
This equipment is normally supplied by protected supplies such as
uninterruptible power supplies, filers or surge suppressors.
Class 2
Applies to points of common coupling (PCCs for consumer systems) and in-
plant points of common coupling (IPCs) in the industrial environment in general.
The compatibility levels in this class are identical to those of public networks.
Class 3
Applies only to IPCs in industrial environments. It has higher compatibility levels
than those of class 2 for some disturbance phenomena. This class should be
considered when any of the following conditions are met:
- a major part of the load is fed through converters
- welding machines are present
- large motors are frequently started
- loads vary rapidly
Testing is not recommended for Class 1 equipment. Test level X specifications are to be agreed
upon by the manufacturer and user. Test Levels for environmental Class 2 and 3 equipment are
defined by the generic standard. A user class X (user) with test level equal or higher than those
of level 2 may be set as well.
California Instruments Revision N 123