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Setup and Panel Instructions 3-5
3.5.2.1.1 E4 exception in
9010F Click
Analyser
According to current standard CISPR 16-1-1, the click analyser should be
able to manage exception E4 (refrigerator rule): "For appliances which
have a click rate less than 5 click/minute, any two disturbances each
having a maximum duration of 200 ms, shall be evaluated as two clicks
even when the separation between the disturbances is less than 200 ms".
At the end of the first run, the 9010F analyses the rate of occurrences. In
case (i) the rate is less than 5 click/minute, and (ii) an "other than click"
(
otc ), a discontinuous disturbance longer than 200 ms, has been
accumulated, the 9010F analyses back whether the otc is made of clicks
separated by less than 200 ms. If this is the case, the otc duration is
reduced by the durations of the two clicks plus the separation between
them. The clicks are sorted and added to the related counters according to
their duration. This is the standard behaviour when the option "Use E4:
Yes" has been chosen. However, the splitting operation affects the click
rate itself. If "Use E4: Y(es) RR" has been chosen in the 9010F, the rate is
then recalculated according to the new click number. If the new rate value
is still below the 5 click/minute threshold, all the above computations are
kept. On the contrary, if the newly calculated rate is equal or higher than 5
click/minute, the described computations are discarded and thus the
original
otc is accounted.
The 9010F operates similarly in the first and the second run when treating
exception E4. However, according to CISPR 14-1 the click rate shall be
evaluated for the first run only,
otcs in the second run are analysed based
upon the rate calculated in the first run.
This way of implementing E4 exception allows the User to be flexible as
desired and thus covering, in the meanwhile, both current standard
interpretation and possible future developments and amendments, without
the need of make any modification.
3.5.3 Calculate Limit
Quartile When the click rate N has been determined, it is possible to calculate the
click limit Lq by increasing the relevant limit (quasi-peak) L for continuous
disturbances with:
●
44 dB for N<0,2, or
●
20 log (30/N) dB for 0,2<N<30
Therefore
N
Log L L
q
30
20
⋅ + =
3.5.4 Measurement vs.
Lq limit Now the test can be done at the 4 fixed frequencies dictated by the
standard: 150 kHz, 500 kHz, 1.4 MHz, 30 MHz, and the results compared
with the limit Lq.
If less than 25% of the clicks measured exceeds the limit Lq, then the test
is positive, otherwise it fails.
The PMM 9010F can now produce an extensive report with all the relevant
data.
The system with PMM CA0010 is able to perform the measurements of the
four channels at the same time, thus saving a lot of time for the job, and
reducing EUT stress.
The PMM Click Analysis software adds an even more detailed test final
report capability.