Panametrics DigitalFlow GC868, Руководство для стартапов

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DigitalFlow™ GC868 Startup Guide (1 and 2-Channel) 1-22
Chapter 1. Installation
Figure 1-33: PDJ Jacket Installation
4. Install the fixture over the jacket, adjusting the spacing to match the
prestamped transducer holes and GC868 spacing calculations.
5. Apply a thin bead of CPL-16 couplant. Spread it in a thin layer about 6 mm (0.25
in.) wide on each transducer face.
6. Install the transducers into the yokes, and tighten the hold-down screws until the
couplant begins to spread.
7. If you wish, reinstall insulation over the pipe, making sure that the yokes and
junction boxes protrude through the pipe.
8. Wait 15 min. for the couplant to cure and finger-tighten the transducer
hold-down screws. Do not use pliers or any other tools.
9. Using a wrench, tighten the transducer hold-down screw backing nuts to
prevent loosening due to vibration and thermal expansion.
1.6 Installing
Temperature
and Pressure
Transmitters
Optional temperature and pressure transmitters may be installed near the
ultrasonic transducer ports as part of the GC868 system. These transmitters can use
a 0/4-20 mA or RTD signal to transmit the temperature and pressure values to the
Model GC868 electronics console. In turn, the electronics console can provide a 24
VDC signal to power the transmitters, if wired in that configuration. Any desired
transmitters or sensors may be used, but they must have an accuracy equal to 0.5%
of the reading or better.
Note: A clamp-on Resistive Thermal Device (RTD) can be used to measure
temperature. It can be wired to either a RTD-to-4-20 mA converter
(separate from the GC868) or directly into an optional RTD input board in the
GC868 (see Figure 1-42 on page 1-43).
Typically, a 1/2” NPT female threaded port is used to mount the transmitters on the
flowcell. If the pipeline is insulated, the coupling may need to be extended to provide
convenient access. Of course, other types of mounting ports, including flanged ports,
may be used for the transmitters.
IMPORTANT: Under changing temperature and pressure conditions, the Model
GC868 can calculate standard volumetric flow accurately only if
temperature and pressure transmitters have been installed.
Figure 1-34 below shows a typical mounting arrangement for the pressure and
temperature transmitters. The temperature sensor should protrude 1/4 to 1/2 way
into the pipe.
WARNING!
The pipe and the dripping fluid will cause severe burns
upon contact with bare skin. Also, be sure not to inhale
the fumes generated during the DMP-3 curing cycle.