3. OPERATION
Page 69
© 1995 - 2010 Fluke Corporation, DH Instruments Division
Note
For to communicate with an RPMx connected to its
COM2 port, the and the RPMx RS-232 interfaces must
be set up properly (see Section 3.6.6.1). If, the is unable
to locate an RPM ON COM2 when running AutoZ by COM2, it times
out after 6 seconds and displays an error message.
If is able to communicate with an RPMx on its COM2 port, the display is:
1.
Real time reading (without head correction) of
upstream (1, Hi) RPT in unit of measure on line 2.
2.
Real time reading (without head correction) of
downstream (2, Lo) RPT in unit of measure on line 2.
3.
Real time reading of the RPMx connected to
COM2 to provide the value of AutoZ
P
offset
.
96.7715U 96.7778D
Pstd,0:96.7752 kPa
Observe the pressure outputs verify that they are stable. A 10 to 15 minute wait,
after venting, is recommended before running AutoZ. When ready, press
[ENT]
to cause AutoZ to run. logs both RPT readings and calculates a new
AutoZ offset value. The display is:
1.
Current/previous value of
P
offset
for the upstream
(1, Hi) RPT.
2.
Current/previous value of
P
offset
for the downstream
(2, Lo) RPT.
3.
New value of
P
offset
for the upstream (1, Hi) RPT for
the AutoZ that was just run.
4.
New value of
P
offset
for the downstream (2, Lo) RPT
for the AutoZ that was just run.
Old: 0.0 Pa 0.0
New: 3.7 Pa 2.6
Press
[ENT]
to activate the new values of
P
offset
or
[ESC]
to start over.
Note
The value of P
offset
is always displayed and entered in Pascal (Pa).
3.4.4.5
<5BPR> (molbloc-S Operation Only)
PURPOSE
To quickly measure the molbloc-S upstream and downstream pressure and
calculate and display the BPR (back pressure ratio) when is in a
molbloc-S BPR mode which would not otherwise measure the BPR.
Note
The <5BPR> menu selection is only present during molbloc-S
operation.
PRINCIPAL
uses the back pressure ratio, or BPR (the ratio of the molbloc-S
downstream absolute pressure to the upstream absolute pressure) to determine
whether the flow through the throat of the molbloc-S Venturi nozzle is critical and
flow measurements within predictable uncertainty limits can be made with
molbloc-S (see Section 3.1.5). When operating with molbloc-S, the
user may select different BPR monitoring modes (see Section 3.6.9). Depending
on which BPR mode is selected, the BPR value is not always measured. The
BPR function allows the user to measure and display BPR directly at any time
regardless of which BPR mode is selected.
