IEC 61326-1-2020 Electrical equipment for measurement, control and laboratory use – EMC requirements – Part 1: General requirements.
Equipment and systems within the scope of this document can be subjected to various kinds of electromagnetic disturbances, sources of which include power, measurement or control lines or those radiated from the environment. The types and levels of disturbances depend on the particular conditions in which the systems, subsystems or equipment are installed and operated. Equipment within the scope of this document can also be a source of electromagnetic disturbances over a wide frequency range.
These disturbances can be conducted through power and signal lines, or be directly radiated, and can affect the performance of other equipment, or influence the external electromagnetic environment. For emissions, the objective of the requirements given in this document is to ensure that the disturbances generated by the equipment and systems, when operated normally, do not exceed a level which could prevent other systems from operating as intended. The emission limits are considered in 7.2.
NOTE 1 Higher immunity levels than those specified can be necessary for particular applications (for example, when reliable operation of the equipment is essential for safety) or when the equipment is intended for use in harsher electromagnetic environments. Also, additional tests and different performance criteria can be necessary for particular applications.
NOTE 2 In special cases, for example when highly susceptible equipment is being used near the EUT, additional mitigation measures could have to be employed to reduce the influencing electromagnetic emission further below the specified limits. The manufacturer may select to perform all tests on either a single EUT or divide the tests among multiple EUTs. If the latter, each test result shall be traceable to the EUT tested. The testing sequence is optional.
5 EMC test plan
5.1 General An EMC test plan shall be established prior to testing. At a minimum, it shall contain the elements defined in 5.2 to 5.5.
It may be determined from consideration of the electrical characteristics and usage of a particular item of equipment that some tests are inappropriate and therefore unnecessary. In such cases, the decision not to test shall be recorded in the EMC test plan.
5.2 Configuration of EUT during testing
5.2.1 General Measurement, control and LABORATORY equipment often consists of systems with no fixed configuration. The kind, number and installation of different subassemblies within the equip- ment may vary from system to system. Thus, it is reasonable, and also recommended, not to test every possible arrangement. To realistically simulate EMC conditions (related both to emission and immunity), the equipment assembly shall represent a typical installation as specified by the manufacturer. Such tests shall be carried out as TYPE TESTS under normal conditions as specified by the manufacturer.
5.2.2 Composition of EUT All equipment, racks, modules, boards, etc. significant to EMC and belonging to the EUT shall be documented. If relevant, the software version shall be documented .
5.2.3 Assembly of EUT If an EUT has a variety of internal and external configurations, the TYPE TESTS shall be made with one or more typical configurations that represent normal use in the intended environment. All types of modules shall be tested at least once. The rationale for this selection shall be documented in the EMC test plan.
5.2.4 I/O PORTS Where there are multiple I/O PORTS , which are all of the same type, connecting a cable to just one of those PORTS is sufficient, provided that it can be shown that the additional cables would not affect the results significantly.
5.2.5 A UXILIARY EQUIPMENT When a variety of equipment is provided for use with the EUT, at least one of each type of equipment shall be selected to simulate actual operating conditions. A UXILIARY EQUIPMENT may be simulated.IEC 61326-1 pdf download.