GE DigitalFlow XMT868i, Руководство для стартапов

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Chapter 1. Installation
4 DigitalFlow™ XMT868i Startup Guide
1.5 Installing Temperature Transmitters
Optional temperature transmitters may be installed as part of the flowcell, near the ultrasonic transducer ports. Be sure
to observe the siting requirements given earlier in this chapter. These transmitters should send a 0/4-20 mA signal to
the Model XMT868i. In turn, the XMT868i must be fitted with a suitable option card to process the signals and to
provide the required 24 VDC power to the transmitters. Any desired transmitters or sensors may be used, but they must
have an accuracy equal to 0.5% of the reading or better.
Note:
Resistive Thermal Devices (RTDs) are a good choice for measuring the temperature.
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.
Figure 2 below shows a typical mounting arrangement for a temperature transmitter. The temperature transmitter
should protrude 1/4 to 1/2 way into the pipe.
Figure 2: Typical Temperature Transmitter Mounting
Transmitter
RTD
Coupling
Thermowell
Flowcell Wall
Temperature