Sensia 3300 EFM, Инструкция по установке, эксплуатации и обслуживанию

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Remote Mount to Orifice Meter or Cone Meter
A MVT can be mounted remotely and connected to an orifice meter or cone meter with tubing for liquid measurement
( Figure 2.19 ). The setup of the meter run and plumbing configurations can vary widely, depending upon the challenges
existing on location.
CAUTION When measuring liquid, process connections must be designed to eliminate air pockets. This is
achieved by mounting the sensor below the metering device and sloping all tubing downward from
the meter to the sensor. A side-port transducer and block manifold (shown in
Figure 2.19
) is recom-
mended to help prevent air bubbles from being trapped in the sensor.
If a bottom-port MVT is used, the bottom process ports must be plugged or replaced with a drain
valve, and side vents must be used for process connections. A block manifold is not recommended
for use with bottom port transducers. Contact a Sensia field representative for assistance.
1. Verify that the meter is properly installed in the flow line (per manufacturer’s instructions).
2. Mount the MVT to a 2-in. pipe using the mounting bosses on the side of the enclosure and a Sensia pole mount kit.
See Multi Variable Transmitter Mounting, page 20 for detailed mounting instructions.
3. Install tubing and fittings to connect the high-pressure and low-pressure taps of the differential pressure meter to the
process connections of the block manifold. Install a pair of shutoff valves near the high and low ports of the differ-
ential pressure meter. Use a suitable compound or tape on all threaded process connections.
4. Install the RTD assembly in the thermowell. A wiring diagram for the RTD assembly is provided in Figure 3.9, page
56 .
RTD assembly
Positioning of sensor below the
meter and slope of tubing helps
prevent gas bubbles from entering
the liquid
Shut-off valves
throttle flow to
the manifold
and MVT
3/4 in. conduit
connection for
input/output &
communications
Figure 2.19 - Remote-mount liquid cone meter run installation. The remote-mount method can be used with an orifice
meter as well.
Note To prevent fittings from turning and/or to avoid putting tension on stainless steel tubing, use a backup wrench to
attach stainless steel tubing to shutoff valves, or sensor ports.
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Section 2 Scanner 3300 EFM