KROHNE OPTIMASS with MFC 300 EN - Manual (Page 129)

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Time Constant
In order to deal with fluctuating flows through the meter, measurements taken from the sen-
sor are digitally filtered in order to stabilise readings. Time constants can be set individually
for each output, display page and density measurement.However, it should be noted that the
degree of filtering affects the response time of the reading due to rapid changes in the flow.
Short time constant
Fast response
Fluctuating reading
Long time constant
Slow response
Stable reading
The time constant represents the sample time for each value. The value displayed or output is
an average value of the preceding sample time.
Dual-Phase Pulse Output
For Custody Transfer applications, it can be necessary to use a dual phase pulse or frequency
output. With this option, a pulse output will be available on terminals B + D or A + B
In this case the following needs to be set:
C3.3.11: Phase shift to D
All functions for output B are set via output A / D
C3.2.11: Sets the phase shift of output B relative to output A. Options are 0, 90 or 180 deg.
C3.5.11: Sets the phase shift of output B relative to output D. Options are 0, 90 or 180 deg.
Timeouts in Edit Mode:
Normal Menu Function: If no key is pressed in a normal menu function for 5 mintes, the display
returns automatically into the measuring mode. All changes made are lost.
Test function: During test mode, the test function is terminated after 60 minutes.
GDC IR interface: If a search for a GDC-IR connection is started, this function will be terminat-
ed after 60 seconds if no connection is found. If the connection is interrupted, after 60 seconds,
the display will work again with the optical keys.
Output Hardware:
Depending on the hardware fitted (see CG No), it may be possible to change the output options
at terminals A, B, C or D in menus C3.1.x
E.G. Pulse output into a frequency output, or a status output into a control input.
Options depend upon hardware fitted. Refer to Section 8.8 for output options.
It is not possible to change output type e.g. from active to passive or Namur.