Chapter 1. Programming Site Data
14
DigitalFlow™ DF868 Multipurpose Ultrasonic Liquid Flowmeter Programming Manual (2-Channel)
Procedure Options
After completing the above steps, the meter returns to the
Channel PROGRAM
prompt. Continue as follows:
•
To continue programming the meter, refer to the menu maps in Appendix A and navigate to the desired menu.
Then, proceed to the appropriate section of this manual for instructions.
•
To leave the
Channel PROGRAM
and retain the previous settings, press
[EXIT]
twice and then press
[F1] = NO at
the SAVE prompt. Any programming changes will be discarded and you will be returned to the data display.
•
To leave the
Channel PROGRAM
and return to measurement mode, press
[EXIT]
twice and then press
[F2] = YES
at
the SAVE prompt. Your programming changes will be entered into the meter’s memory, and you will be
returned to the data display.
1.6.3
Entering Pipe Data
Enter the transducer and pipe parameters via the
PIPE
submenu. While following the programming instructions, see
Figure 10 on page 97 or Figure 11 on page 98
1.
To enter the
Channel PROGRAM
menu, press
[F1]
or
[F2] (the desired channel) at the
User Program
prompt.
2.
Enter the
PIPE
submenu by pressing
[F3]
at the
Channel PROGRAM
prompt.
1.6.3.1
Transducer Number
3.
Enter the
Transducer Number
engraved on the head of the transducer and press
[ENT]
. If there is no engraved
number, complete the steps below. Otherwise, proceed to step 3 on the next page for a clamp-on transducer, or
to step 4 for a wetted transducer.
IMPORTANT:
Special transducers, which have no engraved number on the head, are rarely used. Examine the
transducer head carefully for a number.
a.
Assign a number between 91 and 99 to the
Special Transducer
and press
[ENT]
. (The meter will only accept values
from 1 to 199.)
b.
Use the
[F1]-[F3]
keys to select the
Wedge Type
. Three choices are available: Rayleigh or Shear wave (for
clamp-on transducers) or wetted transducers.
c.
Use the
[F1]-[F3]
keys to select the
Frequency
of the special transducer.
IMPORTANT:
The frequency is required to transmit an excitation voltage at the transducer’s natural frequency.
d.
Enter the special transducer
Time Delay (Tw)
value supplied by the factory and press
[ENT]
.
Note:
Tw is the time required for the transducer signal to travel through the transducer and its cable. This time
delay must be subtracted from the transit times of the upstream and downstream transducers to ensure an
accurate measurement.
If you have selected a special wetted transducer, the meter now rejoins the standard programming sequence.
However, if you have selected a special clamp-on transducer, two additional prompts appear.
e.
Use the numeric keys to enter the
Wedge Angle
(angle of the ultrasonic transmission) in degrees, and press
[ENT]
.
Note:
In TransFlection mode, you must enter a separate wedge angle for both the transmit and receive
transducers.
f.
Use the numeric keys to enter the
Wedge Soundspeed
in ft/sec or m/sec and press
[ENT]
.