GE DigitalFlow GF868, Руководство для стартапов, Страница: 15 / 80

DigitalFlow™ GF868 Startup Guide (1 and 2-Channel) 5
Chapter 1. Installation
1.5 Installing Temperature and Pressure Transmitters
Temperature and pressure transmitters may be installed as part of the flowcell, near the ultrasonic transducer ports. (Be
sure to observe the siting requirements mentioned earlier.) These transmitters must use a 0/4 to 20-mA signal to
transmit temperature and pressure values to the GF868 console. The console, in turn, provides 24-VDC power to the
transmitter. You can use any desired transmitters or sensors; however, they must have an accuracy of 0.5% of the
reading or better.
Note:
Resistive Thermal Devices (RTDs) are typically used to measure temperature.
Typically, a 1/2” or 3/4” NPT female threaded port is used to mount the transmitters on the flowcell. If the pipeline is
insulated, you may need to extend the coupling to provide convenient access. Of course, you may also use other types
of mounting ports, including flanged ports, for the transmitters.
The 4 to 20-mA transmitters typically mount directly into the ports as shown in Figure 2. The temperature sensor
should protrude 1/4 to 1/2 way into the pipe.
Figure 2: Typical Temperature/Pressure Transmitter Mounting
1.6 Mounting the GF868 Enclosure
The standard GF868 is housed in a Type-4X weather-resistant enclosure. Other enclosure options are available, and are
discussed in Appendix C. Refer to Figure 8 on page 17 for standard enclosure mounting dimensions. For meters housed
in one of the optional enclosures, a dimensional drawing will be shipped with the unit.
WARNING! Proper grounding of the GF868 chassis is required to prevent the possibility of
electric shock. See Figure 9 on page 18 to locate the internal ground connection
.
Temperature Transmitter
Pressure Transmitter
Isolation Valve
Flowcell Wall
Coupling
Thermowell
RTD