10-6 Click Mode Operating Instructions10.4.1 Determination ofthe click rateThe first step of the measuring process is to determine the click rate N inthe minimum observation time. This is done measuring the time needed tocount up to 40 clicks or 40 switching operations; the maximum timeallowed is anyway 2 hours (120 minutes), unless the cycle is determinedby a program, which needs additional time to be terminated.Therefore, if the equipment has a cycle and in this cycle less than 40 clicksappear, then the cycle shall be repeated until 40 clicks are counted or untilthe observation time is 2 hours.If the equipment has a cycle and in this cycle more than 40 clicks appear,the observation time is anyway determined by the cycle.When the minimum observation time has been defined, it is possible tocalculate the click rate N using the simple relationship:TnN 1=where n 1 is the number of clicks measured and T is the minimumobservation time.However, in certain conditions – see CISPR 14-1 for further reference –the click rate N must be calculated using a different approach:TfnN ⋅= 2where n 2 is the number of switching operations and f is a factor dictated inthe standard. Such a factor can be taken into account for automaticcalculations if its value is properly set in the main setup page.The click rate shall be determined at two frequencies: 150 kHz (Step 1)and 500 kHz (Step 3).10.4.2 PreliminaryConformity andExceptionsOnce the number of clicks – or switching operations – has beendetermined, then some preliminary controls can be made to verify if therate is greater than 30 (fail conditions); if the measured clicks areconforming to the definition of the standard; if there are exceptionsapplicable.Thanks to its digital architecture, PMM 9010 can easily record and store allthe relevant parameters, keeping trace of all the events occurring duringthe test and allowing the User to post-process all these data; PMM 9010will also notify immediately the test results to the User.10.4.2.1 Old and NewexceptionsThe “Click” test also requires verifying if exceptions E1 to E4 areapplicable. While E1 and E2 are “old” exceptions, easy to deal with, thenew E3 and, in particular, E4 are calling for a new hardware structure: anold click analyzer is no longer compliant.E3 is an additional counter, does not require additional memory andimplies only minor changes in the test flow, thus can be implemented in arelatively easy way.E4 is very demanding in terms of hardware requirements: a memory forstoring each disturbance duration and interval is required in order to post-elaborate them, and it is mandatory to provide all the data in the testreport. Moreover, as the application of E4 is conditional to the final clickrate N - which in turn may prevent using E4 – the test flow significantlychanges.Only new analysers specifically designed – like the PMM 9010 - cansuccessfully meet the requirements of the standard and be compliant withthe new Click test criteria.
