Baker Hughes DigitalFlow XGF868i, Руководство по программированию

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1.6 Entering transducer and pipe parameters
Enter the transducer and pipe parameters via the pipe
submenu. While following the programming instructions,
refer to Figure 28 on page 40 .
1. From the channel program menu, scroll to the pipe
option and press [enter].
2. The first prompt asks for the transducer number .
• For a standard transducer, use the arrow keys to
enter the number engraved on the transducer head,
and press [enter].
• If there is no number engraved on the transducer
head, press the right arrow key to scroll to the
STD option, and use the up and down arrow keys to
change to spec . Then use the arrow keys to enter an
assigned number (from 91 to 99), and press [enter].
IMPORTANT
Special transducers have no engraved number on the
head and are rarely used. Examine the transducer head
carefully for a number.
• If you entered the number for a standard transducer,
proceed to the pipe OD prompt in step 5.
• If you entered the number for a special transducer,
proceed to step 3 below.
1.6.1 Special transducers
NOTE: For special transducers, Panametrics supplies a
transducer data sheet with programming information.
3. Scroll to the transducer
frequency (supplied by the
factory) and press [enter].
NOTE: The frequency is required to transmit an excitation
voltage at the transducer’s natural frequency.
4. Enter the special transducer tw (time delay) value
(supplied by the factory) and press [enter].
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 flow rate measurement.
1.6.2 Pipe data
If either a standard or a special transducer is being used,
the programming sequence should be rejoined at this point.
5. To select the appropriate
pipe OD unit type from
the list shown in Table 3 , scroll to the right side of the
screen, and use the up and down arrow keys to step
through the list. Press [enter]. Then use the arrow
keys to enter the known pipe outside diameter or
circumference on the left side and press [enter].
Obtain the required information by measuring either
the pipe outside diameter (OD) or circumference at the
transducer installation site. The data may also be obtained
from standard pipe size tables found in sound speeds and
pipe size data (914-004).
Table 3: Available pipe size units
English Metric
Inches mm = Millimeters
Feet m = Meters
in/PI = Pipe circumference
in inches
mm/PI = Pipe circumference
in millimeters
ft/PI= Pipe circumference
in feet
m/PI = Pipe circumference
in meters
6. Use the arrow keys to enter the known pipe wall thickness
(in inches or mm) and press [enter]. If the pipe wall
thickness is not available, look up the value in a table
of standard pipe size data which can be found in the
Sound speeds and pipe size data manual (914-004)
IMPORTANT
Because the units cannot be independently chosen for
this parameter, the value must be entered in the same
units used for the pipe OD/circumference.
5