AMETEK MX CTSH - Manual (Page 63)

California Instruments Revision H 63
User Manual MX Series CTSH Compliance Test System
5. Harmonics Testing
5.1 About This Chapter
This chapters covers testing a device for compliance with the IEC 61000-3-12 Harmonics standard. A
review of the possible EUT classes is provided to assist the user in determining the appropriate device
class to use. Once the device class has been established, the appropriate test module is used to perform
the tests.
5.2 Test Selection
The processing of current harmonics is dependent on the selected EUT connection type. (Stage). The user
should determine the nature of the EUT based on his knowledge of the product.
It should be noted that the user must ensure that the total test time applied is sufficient to cover a complete
operating cycle of the EUT.
Note: The user is responsible for selecting the correct connection type and test method for the EUT. The
CTS software does not have any means to determine this based on measuring the EUT current or power.
5.3 Device Test Classes
The IEC 61000-3-12 test standard defines EUT test classes by connection type called stages. The following
connection stages are defined:
Stage Description
Stage 1 Simplified connection
Stage 2 Connection based on network and equipment data
Stage 3 Connection submitted to the local supply authority
Equipment shall be assessed for connection in accordance with the requirements for the three stages
specified above.
Stage 1: Simplified connection
Equipment complying with the harmonic currents emission limits into the public supply system defined for
Stage 1 connection can be connected at any point of the supply system, provided the short-circuit ratio R
sce
is equal to or higher than 33.
Stage 2: Connection based on network and equipment data
For equipment not complying with the emission limits for Stage 1 connection, higher emission values are
allowed, provided the short-circuit ratio R
sce
is > 33.
Stage 3: Connection submitted to the local supply authority
If the conditions of neither stage 1 nor stage 2 are fulfilled, the supply authority may accept the connection
of the equipment on the basis of the predicted effects of such a connection being within the local supply
requirements. This has to be negotiated with the local supply utility by the end user of the EUT.