Rion KS-19F, Инструкция по эксплуатации, Страница: 47 / 62

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Function for cancelling erroneous count
Processing of erroneous counts
If during periodic measurement a given period exhibits an abnormal count,
the erroneous count is replaced by the count from the immediately preced-
ing measurement. During moving average measurement, the moving aver-
age up to the preceding measurement is used to replace the erroneous count
measurement value.
An erroneous count is determined using the following defi nition: a sudden
drastic increase in the signal count over a very short period occurs, and the
ratio between the counts for channel 1 and channel T (channel to which par-
ticle size that is twice the value of the channel 1 is set) is notably different
from normal particle size distribution.
When both following condition 1 and condition 2 are approved, it is judged
an erroneous count.
- Condition 1
The count value
C
N
of channel 1 in one measurement is higher by a
factor of 20 or more than the moving average value
C
MA
of the im-
mediately preceding measurement.
(If the moving average is less than 0.2, it is considered to be 0.2.)
- Condition 2
The ratio between the channel 1 count
C
ch1
and the channel T count
C
chT
for one measurement is 20 or higher
(If the channel T count
C
chT
for this measurement is 0, condition 2
applies if the channel 1 count
C
ch1
is 4 or higher.)
The erroneous count event can occur up to twice continuously but if the event
occurs three times or more consecutively, the erroneous count processing
function will stop. When the erroneous processing stop, the raw measure-
ment data will be outputted with “NOISE HIGH” message to the CF card,
the printer or the serial interface.
C
N
C
MA
20
C
ch1
C
chT
20