Siemens SITRANS FUS1020, Manual, Page: 159 / 251

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1020NFM-1D
Section 6
6.6.6 TOTALIZER SCALE
After you select totalizer units, the meter automatically computes a prefix to provide the best combina-
tion of capacity and resolution (e.g., MGAL/MIN). The [Totalizer Scale] menu cell shows the results. If
the displayed scaling is not suitable, you can edit it by accessing the option list. Note that this scaling
applies to all flow total data displayed on the flow display screen, even if the units do not appear next to
the data (because there may not be room on the screen). Always keep this prefix in mind when you
enter totalizer-related data.
To select a different Totalizer Scale:
To access the [Totalizer Scale] option list press the <Right Arrow>.
Move the cursor to the desired display scale press the <Up/Down Arrows>.
To register selection press <ENTER>.
6.6.7 TOTAL RESOLUTION
The meter assigns multiplier prefixes for the flow total units you selected (e.g., MGPM). It provides
three resolution (or capacity) levels. Therefore, actual Totalizer display units depend on the selected
multiplier. Check the total units by accessing the [Totalizer Scale] menu cell.
If you use the totalizer (TOTCNT) relay output, take into account:
a) The TOTCNT relay output pulses at a maximum rate of .5 pulse per second (.5 Hz).
b) The meter sends a totalizer output pulse for every advance of the rightmost visible totalizer digit.
It is possible for a high flow rate to persist long enough to exceed the relay output’s .5 Hz rate. If this
occurs, the meter will store excess pulses in an overflow buffer, and route them back to the relay when
the flow rate drops enough to allow the TOTCNT output to catch-up. Exceeding the .5 Hz rate for long
periods could cause an excessive accumulation of buffered pulses and continue to trip the relay after
the flow rate lessens, or even stops. If this occurs, the meter will be unable to indicate the current flow
total. Therefore,
select a resolution to ensure that, even at the maximum expected flow rate, the TOTCNT
pulse will not be activated more than .5 times per second for any appreciable length of time . Note that
resetting the Totalizer also clears the overflow buffer.
To change the default resolution:
To access the [Total Resolution] option list press the <Right Arrow>.
Move the cursor to the required resolution by pressing the <Up/Down Arrows>.
To store selection press <ENTER>.