Siemens SITRANS FUH1010PVDX, Operating Instructions Manual, Page: 128 / 308

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CQO:1010PVXFM-3 Section 5
5.4.6 THE NUMBER INDEX MENU CELL
Selecting the [Spacing Offset] menu cell allows the flow computer to calculate the Number Index. The
Number Index establishes the spacing between a pair of transducers. You cannot override this recom-
mendation. To complete the transducer installation, you must accept the Number Index by mounting the
transducer at that point on your spacer bar or mounting track. Initially, the flow computer bases its Num-
ber Index selection on the pipe diameter and estimated liquid sonic velocity (Vs) you entered in the Pipe
Data menu. When you invoke the [Install Completed?] routine, the flow computer actually measures the
liquid sonic velocity (Vs). In some cases, it may prompt you to re-space the transducers to another
number index.
5.4.7 THE Ltn MENU CELL
This view only menu cell shows the distance in inches or millimeters between the front faces of the
transducers along the axis of the pipe. If you are mounting the transducers without a track or spacer bar,
you have to space them according to this value. Note that Ltn may be a negative number for direct mount
on very small pipes where the transducer spacing overlaps.
5.4.8 HOW TO USE [INSTALL COMPLETE?]
Use the [Install Complete?] menu cell to inform the flow computer that you have mounted the transduc-
ers according to the selected mode and spacing requirements and are ready to start operation.
To start the [Install Complete?] routine for an original installation:
Select any transit-time mode (e.g., Clamp-On or Flow Tube) and press the <Right Arrow>.
Press <Down Arrow> and scroll to the [Pick/Install Xdcr] menu cell. Press <Right Arrow>.
Install transducers as required (refer to Section 3 for procedures).
After transducers are properly mounted, the flow computer completes its Initial Makeup command and
the [Install Complete?] menu cell appears.
To access the [Install Complete?] option list, press the <Right Arrow>.
NOTES
Mount the transducers using the selected mode (direct or reflect). Please refer to the
transducer mounting procedures detailed in Section 3.
When using a mounting track or a spacer bar in reflect mode, locate the first trans-
ducer at the Reference Index and the second transducer at the recommended Number
Index.
If you are mounting the transducers independently, you must use the recommended
distance; Ltn to space the transducers.
You must use the proper sonic coupling compound. See “Recommended Sonic Coupling
Compounds” in Section 3 for appropriate type and part number.
The pipe must be completely filled with a liquid, which can be either flowing or at zero
flow
.