AMETEK MX CTSH - Manual (Page 118)

User Manual MX Series CTSH Compliance Test System
California Instruments Revision G 115
12.4 Test Levels
In Annex B of the draft standard, the EUT operating environment classifications are defined based on IEC
61000-2-4. The classifications are as follows:
Class Environment
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 2, 3 and 4 defined in the standard are applied to environmental
Class 2 and 3 equipment. Test Level 3 is defined for interconnected networks and Level 4 for non-
interconnected networks (islands for example) where the frequency variations can be much higher. The
following table summarizes the EMC classes and test level relationships.
Test Level Environment classification Frequency Variation
Level 1 Class 1 No test required
Level 2 Class 2 ± 3 % of Fnom
Level 3 Class 3 and 4 used in interconnected networks + 4 % and - 6 % of Fnom
Level 4 Class 3 and 4 used in non-interconnected networks ± 15 % of Fnom
Level X Product class specific Open but must be higher
than test level 2.
12.5 Test Options
The voltage regulation of the AC Source can be verified by selecting the "Include Source Regulation
Check" check box. This will cause the AC load to measure its output using the built in measurement
system at all the frequency extremes that will be applied to the EUT during the test. The measured output
voltage must be within the source regulation limits specific in the EN 61000-4-28 standard. If so, a PASS
indication will be shown in green to the right of the option box. If not, a FAIL indication will be shown in red.
If the source regulation check fails, check the system connections. For higher power loads, make sure the
external sense lines are used to sense the voltage at the EUT terminals.
Tests are started using the Start button or the Run, All menu.