IEC 61000-4-11-2020 ELECTROMAGNETIC COMPATIBILITY (EMC) – Part 4-11: Testing and measurement techniques – Voltage dips, short interruptions and voltage variations immunity tests for equipment with input current up to 16 A per phase.
4 General
Electrical and electronic equipment can be affected by voltage dips, short interruptions or voltage variations of the power supply.
Voltage dips and short interruptions occur due to faults in a (public or non-public) network or in installations by sudden changes of large loads. In certain cases, two or more consecutive dips or interruptions can occur. Voltage variations are caused by continuously varying loads connected to the network.
These phenomena are random in nature and can be minimally characterized for the purpose of laboratory simulation in terms of the deviation from the rated voltage and duration.
Consequently, different types of tests are specified in this document to simulate the effects of abrupt voltage change. These tests are to be used only for particular and justified cases, under the responsibility of product specification or product committees.
It is the responsibility of the product committees to establish which phenomena among the ones considered in this document are relevant and to decide on the applicability of the test.
5 Test levels
5.1 General
The voltages in this document use the rated voltage for the equipment (U T ) as a basis for the voltage test level specification.
Where the equipment has a rated voltage range the following shall apply:
• if the voltage range does not exceed 20 % of the lower voltage specified for the rated voltage range, a single voltage within that range may be specified as a basis for the test level specification (U T );
• in all other cases, the test procedure shall be applied for both the lowest and highest voltages declared in the voltage range;
• guidance for the selection of test levels and durations is given in IEC TR 61 000-2-8.
5.2 Voltage dips and short interruptions
The change between U T and the changed voltage is abrupt. The step can start and stop at any phase angle on the mains voltage. The following test voltage levels (in % U T ) are used: 0 %, 40 %, 70 % and 80 %, corresponding to dips with residual voltages of 0 %, 40 %, 70 % and 80 %.
For voltage dips, the preferred test levels and durations are given in Table 1 , and an example is shown in Figure 1 a) and Figure 1 b).IEC 61000-4-11 dpf download.