GE DigitalFlow DF868, Руководство для стартапов

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Chapter 2. Initial Setup
24 DigitalFlow™ Multipurpose Ultrasonic Liquid Flowmeter Startup Guide (1- and 2-Channel)
2.6 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.
2.6.1 Transducer Number
2. 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 (the 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 transducer and the receive
transducer.
f. Use the numeric keys to enter the Wedge Soundspeed in ft/sec or m/sec and press
[ENT]
.