Reynolds Correction; Calibration Factor - GE DigitalFlow DF868 Startup Manual

Chapter 2. Initial Setup

2.6.9 Reynolds Correction

[F1]
11. Press to turn Reynolds Correction off, or
Note: Reynolds Correction is a number based on the Kinematic Viscosity and flow rate of the fluid. It should be
enabled for most applications.
12. When you enable the Reynolds Correction Factor, you must also enter the Kinematic Viscosity of your fluid, as
listed in Sound Speeds and Pipe Size Data. Use the numeric keys to enter a value, and press

2.6.10 Calibration Factor

13. Enter a value for the flow Calibration Factor and press
and 2.00 may be entered.
14. The menu now varies, depending on whether you have activated the TransFlection or Transit-Time mode.
•
If you activated the TransFlection mode, the program asks for the Depth of Reflector. This setting determines where
in the pipe the DF868 looks for the reflected signal. The default value is 50%. Use the numeric keys to enter a
[ENT].
value, and press
Note: GE recommends activating the Reynolds Correction Factor when the Depth of Reflector is set at 50%. You can
disable the Reynolds Correction Factor when the Depth of Reflector is set at any other value.
•
If you activated the Transit-Time mode, two steps appear.
[F1]-[F4]
a. Use the keys to select the desired Number of Traverses, the number of times the ultrasonic signal
traverses the pipe, from 1 to 5.
b. The Transducer Spacing prompt displays the spacing of the transducers, as calculated from the information you
have entered. Record this number and use it to properly space transducers.
Note: If necessary, you can overwrite the spacing shown (using the numeric keys) to match the actual physical
spacing of the transducers. The factory does not recommend overwriting the spacing. If you must, do not
change the spacing by more than ±10% from the value shown.
You have completed entering pipe parameters for clamp-on transducers. Press
[EXIT]
submenu, and to leave the submenu.
Table 12 lists the numeric parameters in the
28
[F2]
PIPE
submenu, with their high and low limits.
Table 12: Low and High Limits for PIPE Parameters
Parameter
Wedge Angle
Pipe OD
Pipe Wall
Lining Thickness
Kinematic Viscosity
Path Length
Axial Length
DigitalFlow™ Multipurpose Ultrasonic Liquid Flowmeter Startup Guide (1- and 2-Channel)
to turn it on.
[ENT]
. The default value is 1.00, but values between 0.50
Low Limit High Limit
25°
0.12 in.
0 in.
0 in.
0.1
10,000 (E-6 ft
0.12 in.
0.12 in.
[ENT].
[ENT]
to return to the start of the
90°
300 in.
4.0 in.
4.0 in.
2
/s)
480 in.
480 in.
PIPE