Micro Motion Fisher-Rosemount RFT9709, Instruction Manual

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RFT9709 Transmitter Instruction Manual
11
Wiring
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Remotely-installed
temperature detector A temperature signal is transmitted to the RFT9709 from a temperature
detector (RTD) on the flow tube inside the sensor case. This signal is
carried by three wires of the flowmeter cable: the yellow, orange and
violet wires (see Table 2-1, page 13).
To meet API requirements, a user-supplied external temperature
detector can be installed remotely by the user. This external temperature
detector, instead of the RTD inside the sensor, is wired to the RFT9709.
• The external RTD must be accurate to ±0.1°F (±0.05°C).
• RTD calibration information must be configured in the RFT9709.
Requirements for installing a user-supplied external temperature
detector:
• Locate the external temperature detector as close to the sensor as
possible.
• Use an individually shielded 3-wire cable of 22 AWG (0.3 mm²) or
larger wires to connect the external temperature detector to the
flowmeter.
• Wiring diagrams are provided in Figure 2-6, Figure 2-7, and Figure 2-8
on pages 14 through16.
Procedure for installing the user-supplied external temperature
detector:
1. At the sensor junction box, before connecting the flowmeter cable,
identify the yellow, orange and violet wires that come from inside the
sensor.
2. Disconnect these wires from the terminal block, and tie all three
together with a wire nut to protect exposed wire ends.
3. Connect three wires from the external temperature detector to the
terminals, as illustrated in Figure 2-6, Figure 2-7, or Figure 2-8. If the
temperature detector has a fourth wire, it remains unconnected.
4. Make flowmeter cable connections as illustrated in Figure 2-6,
Figure 2-7, or Figure 2-8.
09wire.fm Page 11 Monday, March 1, 1999 4:31 PM