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Select: Measure Mode:
Continuous: Continuous measurement; standard setting for most measurements.
With this type of measurement, a sliding average is calculated over the
selected time constant.
Batchmode Batch measurement with external start-stop signal (digital input 22a and
22c)
or via the <run> button.
We recommend using the “Batch measurement” mode, for example,
when a pipeline or container is filled briefly and then emptied again. In
this case, shorter measuring times can be used.
During batch measurement an arithmetic mean is calculated over the
measurement time.
To start a measurement process, either push the <run> button or
briefly connect terminals 22a /22c.
A measurement stops as soon as the entered measurement time is over
(time constant). The shortest batch time that can be used is approx. 2 s.
or if you push the <run> button again.
Time constant:
Enter the time constant of the instrument system. It determines the average calculation
of the counts supplied by the detector. In order to reduce statistical variations, you
should select the highest time constant that is still permissible. It is dependent upon the
permissible error during the maximum possible density changing speed. A time constant
of less than 20 seconds will therefore be required only in exceptional cases. Typical input
values are between 30 and 300 s.
A measurement time can be preset for batch measurement. Once this time is over, the
measurement stops automatically. The shortest batch time is approx. 2 s.
Rapid switchover:
OFF / ON: This function (= 1/10 of defined time constant) is needed to adjust the out-
put signal quickly to the new value if sudden density changes occur.
Sigma Sigma defines a range (window) which the display change has to exceed be-
fore the selected time constant automatically switches over to a value that is
smaller by a factor of 10 (max. 0.8 sec).
When using the rapid switchover function, you should at least enter “4” or
better “5” as Sigma value to make sure that a switchover of the time con-
stant is not triggered too often by statistical variations or minor density
changes. We recommend determining the optimum entry during routine op-
eration (see also chapter 8.3 Automatic Measuring Time Switchover).
Radiating interference:
This function is needed only when unforeseeable influences due to interfering radiation
are to be expected. It is enabled and disabled via <ON> and <OFF>.
Sigma defines a limit value which the display change has to exceed before the measure-
ment is aborted. The value has to be set such that short-term density variations occur-
ring during operation do not trigger this function.
Enabling radiating interference detection disables the rapid switchover function.
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