PF-10540 belongs to the test method series of this North American manufacturer, and its role is complementary to the requirement documents rather than alternative to them: where a requirement states the disturbance a component must tolerate, a test method states how the disturbance is generated, applied and measured, and the two are cited together. The separation is sensible in an organisation with several test houses, because it allows the procedure to be controlled centrally while the limits are set per programme. In practice the method document fixes the generator and its waveform, the coupling or field application arrangement, the configuration of the equipment under test and the measurement to be recorded, and the requirement document fixes the level. A supplier preparing a test plan should map each clause of the requirement to the method that implements it. The superseded DaimlerChrysler designation of the same number should be treated as the same document.