Zeromatic (Optional Function) - Siemens SITRANS F Instruction Manual

Section 2
The meter begins to measure the positive flow rate. "Positive" flow refers to flow moving from up-
z
stream transducer location to the downstream transducer location. Note top prompt line shows:
Reversamatic Action
Upon completion, the meter beeps and the display screen shows:
z
Now remove then remount the upstream and downstream transducers in their reversed positions.
z
Mount the Up transducer (without removing its cable) in the Down transducer/cable location. Mount
Down transducer with its cable in the Up transducer/cable location. When remounting the transduc-
ers, couple them to the pipe properly. Press <ENT> (after re-installing the transducers).
The flow computer measures the negative flow rate briefly, then beeps and repeats the
z
Reverse Xdcrs/Press ENT
Now remount the transducers for normal operation (in their original orientation). When remounting
z
transducers, couple them to the pipe properly. Press <ENT> (after re-installing the transducers).
This completes the ReversaMatic procedure. The system's zero accuracy will be very close to that obtain-
able using the Actual Zero method, providing flow remained constant during this procedure.
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.

2.4.11 ZeroMatic (optional function)

NOTE: ZeroMatic is used in the Reflect Mode only.
Use this menu cell to select the ZeroMatic option. If conditions permit the use of the Auto Zero function
then the ZeroMatic option can be used as well.
To select and enable the ZeroMatic option:
In the [Pick/Install Xdcr] menu, press
To access the [Zero Flow Adjust] option list press
NOTE: If ZeroMatic is not running, the [Actual Zero] menu item will be displayed next to the
[Zero Flow Adjust] menu cell.
Reverse Xdcrs/Press ENT
prompt.
REYNOLDS TABLE
to scroll to the [Zero Flow Adjust] menu cell.
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