Using Actual Zero; Using Reversamatic - Siemens SITRANS FUH1010PVDX Operating Instructions Manual

Section 5

Using Actual Zero

NOTE: Flow must be stopped with the line blocked (if possible) before invoking this function.
To invoke Actual Zero:
Access the [Zero Flow Adjust] option list by pressing
ENT
Press . A pop-up window prompts you to set the current flow rate (in selected rate units) to
equal zero (0.000).
NOTE: If a flow offset is desired (i.e., to test analog outputs) then press <Right Arrow> to enable
numeric entry.
Press to start the Actual Zero process.
ENT
When you send the command, the flow computer analyzes the current flow rate for up to sixty seconds,
integrating (averaging) the data for the best zero correlation. During this time, the menu prompt at the
top of the display screen shows a timer that counts from zero to sixty. You can allow zero averaging for
the entire period, or cancel the process at any time by pressing the <ENT> key. This controls the amount
of data the meter averages to obtain a zero level.

Using ReversaMatic

If site conditions do not permit stopping the flow rate at the mounting location, and you do not know the
current flow rate, then you can use the ReversaMatic routine to establish the zero flow level. You should
perform the ReversaMatic procedure as quickly as possible to ensure that the flow rate remains constant
throughout the procedure.
To invoke ReversaMatic:
To access the [Zero Flow Adjust] option list press
Move the cursor to [ReversaMatic]. Press
The meter begins to measure the positive flow rate. "Positive" flow refers to flow moving from up-
stream transducer location to the downstream transducer location. Note top prompt line shows:
Upon completion, the meter beeps and the display screen shows:
Now remove then remount the upstream and downstream transducers in their reversed positions.
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 prompt:
Now remount the transducers for normal operation (in their original orientation). When remounting
transducers, couple them to the pipe properly. Press <ENT> (after re-installing the transducers).
to invoke the routine.
ENT
Reversamatic Action
Reverse Xdcrs / Press ENT
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CQO:1010PVXFM-3
Reverse Xdcrs / Press ENT