Hiflow And Loflow; Ancal - Siemens SITRANS F Instruction Manual

Section 2
Vs m/s
This menu cell shows the current sonic velocity in m/s. If you move the cursor to this menu cell you will
note that it switches from the usual arrow (
increase the reading by pressing the [+] key for coarse adjustment or the [1] key; for fine adjustment; or
reduce the reading by pressing the [-] key for coarse adjustment or the [2] key for fine adjustment. The
pipe diameter and transmission frequency determines the effective increase or decrease per key press.
Sonic velocity (Vs) adjustment is a diagnostic tool intended for our technicians or experienced users only.
Improper use will affect the meter accuracy.

HiFlow and LoFlow

The [HiFlow] and [LoFlow] menu cells allow you to enter maximum and minimum expected flow rates
based on current operating conditions. Under normal circumstances, you should never need to change
these settings. It is possible, however, that a Siemens customer service engineer may ask you to edit
these settings during a support session. In such a case, a <Right Arrow> at the menu cell enables
numeric entry.
Important Note: A caution on the use of upper and lower flow limits (used to prevent flow mis-
registration) prior to using the Reversal Zero technique (Reversamatic): If the negative flow rate
that the meter reads in the step during which the transducers are reversed is more negative than
the lower flow limit, the meter will re-register positive and the Reversal Zero cycle will thus be
corrupted.
Therefore, postpone the installation of upper and lower flow limits until the reversal zero proce-
dure is executed successfully. For pipes that combine large diameters with very high flow veloci-
ties, it may be necessary to move the upper and lower flow limits out of the way until the reversal
zero is completed. Moreover, pipes of this size frequently have excellent intrinsic zero perfor-
mance and may not even need zeroing.

AnCal

This menu cell allows you to enter an artificial flow rate in current rate units that will drive the meter's
analog outputs, totalizer output and the screen shown below. You can use AnCal to check the analog
outputs or as a reference source for calibrating external devices such as remote display screens or chart
recorders and RTU's. To test the Totalizer function, leave AnCal active for enough time for an accumula-
tion to appear on the screen below. Moving the cursor from the menu cell cancels the AnCal function.
The M status is
asserted due to the
method used to
simulate flow data.
) to a question mark (?). This indicates that you can
→
Siemens 2 Channel [1]
Flow Rate Simulation Control
Flow GAL/MIN
Velocity F/S
Total GAL
Vs m/s
Signal mV
Valc %
Vaer %
Alarm Status
AnCal GAL/MIN
HiFlow GAL/MIN
LoFlow GAL/MIN
Flow Data
2-70
1
120.00
0.000
5645.820
1274.33
44
57
13
------M--
> 120.000
1577.9
-1577.9
1010ENFM-3B
Note that the [Flow]
menu cell immediately
reflects the AnCal entry.
Over time, the Total
display will also
increase.