Sensia 3300 EFM, Инструкция по установке, эксплуатации и обслуживанию

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Installation Procedure—Direct Mount to Orifice Meter or Cone Meter
A MVT can be mounted directly to an orifice meter or cone meter for gas measurement. The setup of the meter run and
plumbing configurations can vary widely, depending upon the challenges existing on location. Figure 2.11 shows a typi-
cal direct-mount installation.
Flow
RTD assembly
Orifice flanges
3/4” conduit connection
(for input/output and
communications)
5-valve
manifold
Pressure ports
(high/low)
H L
L H
Mounting
adapter
Figure 2.11 - Direct-mount installation in an orifice meter run (shown here with an orifice meter). The direct-mount method
can be used with a cone meter as well.
1. Verify that the meter is properly installed in the flow line (per manufacturer’s instructions).
2. Connect the MVT and manifold assembly to the differential pressure meter. Hardware requirements will vary,
depending upon the installation configuration. However, minimally, an adapter is required that can span between the
threaded pressure tap/orifice flange connector and the non-threaded manifold. This adapter can be a one-piece sta-
bilizer (often preferred for added strength and stability) or a short heavy wall pipe nipple attached to a futbol flange
(available from Sensia). Use a suitable compound or tape on all threaded process connections.
CAUTION Do not use Teflon tape on the threads of the union, adapter, or pipe plugs. Use of
Teflon tape will void the explosion-proof rating of the instrument.
3. Install the RTD assembly in the thermowell. Route the RTD assembly cable through the conduit opening in the top
of the MVT to connect to the main circuit board. A wiring diagram for the RTD assembly is provided in Figure 3.9,
page 56 .
4. Follow guidelines outlined in MVT manual to perform a manifold leak test.
5. Wire outputs or COM connections from the MVT to the inputs or COM connections on the back of the Scanner
3300.
6. Verify the zero offset (and other calibration points), if required.
CAUTION Do not put the MVT into operation until the valves are positioned properly so that pressure is sup-
plied to both sides of the transducer.
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Scanner 3300 EFM Section 2