This method is used to define the immunity of electric and electronic apparatus and equipment (products) to radiated electromagnetic (EM) energy.
This method is based on injecting the calibrated radio frequency currents (voltages) into external conductors and/or internal circuits of the product under test, measuring the strength of the EM field generated by this product and evaluating its immunity to the external EM field on the basis of the data obtained.
The method can be utilized only when it is physically possible to connect the injector to the conductors and/or circuits mentioned before.
The method allows:
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Evaluating immunity of the product under test to external EM fields of the strength equal to a normalized one;
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Calculating the level of external EM field strength at which the given (including maximum permissible) induced currents or voltages are generated in the equipment under test, or solving the “opposite” task;
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Finding potentially “weak” points of the product design (housing, shield, etc.), through which EM energy can enter inside the product.
The method capabilities mentioned above define the sphere of its application:
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Measurements of electronic product immunity to external EM fields at different conditions (polygons, laboratories, in-situ) as an alternative to direct test methods;
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Operating instruments for a designer working out the product of a given immunity to external EM fields.
This method can’t be directly applied to evaluate the immunity of the equipment under test to the pulse electromagnetic fields. But it can be used to get the initial data necessary to solve this task.