GE DigitalFlow GS868, Руководство для стартапов

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Initial Setup 2-7
March 2008
Entering Pipe Data
The
PIPE
submenu permits entry of the transducer and pipe
specifications. To program this menu, complete the following steps:
1.
At the User (or Channel) Program screen, press
[F3]
to program
the
PIPE
submenu.
Transducer Number
2.
Enter the Transducer Number (normally engraved on the head of
the transducer). Press
[ENT]
. If there is no engraved number,
complete the steps below. Otherwise, proceed to step 3.
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 [
→]
and
[F1]-[F4]
keys to select the Frequency of the
special transducer. The meter can not transmit an excitation
voltage at the transducer’s natural frequency without this data.
c.
Enter the special transducer Time Delay (Tw) value supplied by
the factory. Press
[ENT]
. (The meter will only accept values
from 0 to 1000
μ
sec.)
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.
Pipe OD
3.
Enter the known Pipe OD or circumference and use the
[F1]-[F4]
keys to select the appropriate units. Press
[ENT].
(The meter will
only accept values from 1/8 to 648 in.) The option bar choices
may appear in English or Metric units.
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.
Table 2-4 below lists the available English and metric OD units.
Table 2-4: Available Pipe OD Units
English Metric
inch = pipe OD in inches mm = pipe OD in millimeters
feet = pipe OD in feet m = pipe OD in 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