Chapter 1. Programming Site Data
16
DigitalFlow™ DF868 Multipurpose Ultrasonic Liquid Flowmeter Programming Manual (2-Channel)
1.6.3.4
Pipe Wall
6.
Enter the known thickness of the
Pipe Wall
, in the same units used for the pipe OD, and press
[ENT]
.
IMPORTANT:
Because the units can not be independently chosen for this parameter, the value must be entered in the
same units used for the pipe OD.
If the pipe wall thickness is not available, look up the value in a table of standard pipe size data (such as the
Panametrics brochure
Sound Speeds and Pipe Size Data,
914-004), or use the Model DF868’s on-line
Help Menu
(see
the
Programming Manual
for details).
For wetted transducers, skip to step 7.
1.6.3.5
Lining
7.
Press
[F1]
if the pipe does not have a
Lining
, or
[F2]
if it does have a lining. If you select YES, complete the steps
below.
a.
Use the
[F1]-[F4]
and [
keys to select the
Lining Material
. Options include Tar, Pyrex, Asbestos, Mortar, Rubber,
PTFE and Other. If you choose “OTHER,” the DF868 then asks you to enter the lining sound speed. If you do not know
the lining sound speed,
Sound Speeds and Pipe Size Data
(914-004)
lists some standard materials and their
corresponding sound speeds.
b.
Enter the known
Lining Thickness
, in the same units used for the pipe OD. Press
[ENT]
. Then proceed to step 9.
1.6.3.6
Path and Axial Length
8.
Enter the
Path Length
of the ultrasonic signal. Press
[F1]
or
[F2]
to select the desired units, and press
[ENT]
.
Note:
The factory has calculated both the transducer signal path length
(P)
and the transducer signal axial length
(L)
, based on the exact transducer configuration used for the application. These values are engraved on the
flowcell and/or are included in the documentation supplied with the meter. See Appendix D for an
explanation as to how these values are calculated.
9.
The next prompt varies, depending on whether you selected Transit-Time or TransFlection in the
ACTIV
menu.
•
If you selected Transit-Time, the DF868 asks for the
Axial Length
. Enter the supplied value. Press
[F1]
or
[F2]
to
select the desired units, and press
[ENT]
.
•
If you have selected TransFlection, enter the number of degrees for the
Transducer Angle
, and press
[ENT]
. Skip
to step 10.