Siemens SITRANS FUH1010PVDX, Руководство по эксплуатации, Страница: 146 / 308

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CQO:1010PVXFM-3 Section 5
NOTE: NETFLOW (default) is best for applications where there may be zero flow for long peri-
ods. It minimizes false Totalizer register increments due to data scatter. Press the <Down
Arrow> to accept the default setting.
To select a Totalizer Mode:
To access the [Totalizer Mode] option list press
Move the cursor to the required Totalizer mode by pressing
To store selection press
5.6.9 BATCH/SAMPLE TOTAL
The meter maintains a separate totalizer register for Batching or Sampling applications. Unlike the Flow
Total registers, you cannot access this register directly. It is used for relay control only. If you assign the
system relay to this function, a momentary (200 mS) relay pulse occurs whenever the BATCHTOT
register accumulates a specified liquid quantity. You enter the total flow volume required to activate the
relay, in the [Batch/Sample Total] menu cell. The numeric entry must reflect the selected flow total units.
The [Totalizer Display Scaling] menu cell shows the applicable flow total units. The sign of the Batch/
Sample Total determines positive or negative accumulation.
NOTE: The Batch/Sample total relay requires the same consideration for exceeding the maxi-
mum pulse rate as the TOTCNT relay (see paragraph 5.6.7 Total Resolution).
ENT
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
Move the cursor to the required resolution by pressing
To store selection press
ENT
MODE FLOW DIRECTION NOTES
POSFLOW positive flow Accumulates flow in positive direction only.
NEGFLOW negative flow Accumulates flow in reverse direction only.
NETFLOW positive or negative Adds to positive total; subtracts from reverse total.
5.6.8 TOTALIZER MODE
The Totalizer function operates in any of the modes listed below: