BS 62041:2010 pdf download – Safety of transformers, reactors, power supply units and combinations thereof — EMC requirements
The relevant ports of the EUT shall be subjected to the required test in accordance with the applicable subclauses. Tests shall be carried out only when the relevant ports exist. Tests shall be conducted under the no-load condition at the rated voltage and the rated frequency, unless otherwise specified in the generic EMC standard as indicated in Clause 5. If EUT is not intended to operate under the no load condition, for some tests, a load may need to be applied for perturbation.
In this case, the specification of the load shall be stated in the test report. Tests shall be conducted sequentially. The sequence of testing is optional. The necessity to conduct some of the tests may be determined in accordance with the electrical characteristics and the specific application of the particular transformer. In such cases the rationale for not conducting the tests shall be stated in the test report.
The description of the tests, the test generator, the test methods and the test set-up are specified in the generic EMC standard for testing in accordance with Clause 5. The tests are carried out following the manufacturer’s documentation. This includes a functional description and explanation of performance criteria, during or as a consequence of the EMC testing.
This shall be provided by the manufacturer and included in the test report, based on the following criteria. In case of no documentation, necessary conductors, the cross section, the type and the length of the conductors used shall be reported in the test report. Performance criterion A: The EUT shall continue to operate as intended during and after the test. No degradation of performance or loss of function is allowed below a performance level specified by the manufacturer, when the EUT is used as intended. The performance level may be replaced by a permissible loss of performance.
If the minimum performance level or the permissible performance loss is not specified by the manufacturer, either of these may be derived from the product description and documentation and what the user may reasonably expect from the EUT if used as intended.
Performance criterion B: The EUT shall continue to operate as intended after the test. No degradation of performance or loss of function is allowed below a performance level specified by the manufacturer, when the EUT is used as intended. The performance level may be replaced by a permissible loss of performance. During the test, degradation of performance is, however, allowed. No change of actual operating state or stored data is allowed. If the minimum performance level or the permissible performance loss is not specified by the manufacturer, either of these may be derived from the product description and documentation and what the user may reasonably expect from the EUT if used as intended. Performance criterion C: Temporary loss of function is allowed, provided the function is self- recoverable or can be restored by the operation of the controls. If, as a result of the application of the tests defined in this standard, the transformer becomes dangerous or unsafe (e.g., by an insulation breakdown), the EUT is deemed to have failed the tests.
5.1 .2 Test levels
5.1 .2.1 General Levels for test stated in this standard correspond to typical condition for environment 1 and 2. However, if special conditions prevail for the use of the final product, the relevant values in the basic standard shall be applied and stated in the test report.
5.1 .2.2 Electrostatic discharges These tests are carried out according to IEC 61 000-4-2, with test levels as given in Table 1 . Except for metallic parts for which a contact discharge test is made, only air discharge test is required. Ten positive and ten negative pulses shall be applied to each selected point. The time interval between each successive single discharge is 1 s.