Emerson Daniel Series, Руководство пользователя

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LME - High temperature
The LME - High temperature consists of an electrical enclosure and a solid cover both
made of stainless steel. This configuration contains one mounting bracket and two high
temperature terminal blocks which are the connections between the high temperature
pickoff coils and the flex cable.
Important
The customer provides and installs a flex cable.
The flex cable is the connection between the preamplifier that is assembled into a Remote
Mounted Enclosure (RME), not more than 6 meters from the center of the meter housing
to the center of the RME.
The electrical enclosure contains an external and an internal grounding lug. The two
enclosure openings are plugged. Refer to
Operating conditions and specifications .
Remote Mounted Enclosure (RME)
The RME is an electric transmitting device used primarily in the petroleum industry for
remote installation of liquid turbine meter electronics. The RME is specifically designed for
high temperature applications.
The turbine meter is ideal for applications requiring high frequency resolution.
Applications may include electronic registers or flow computers.
1.2.2 Operation overview of the turbine meter
Metering systems combine turbine meters and electronic instrumentation to measure
volumetric total flow and/or flow rate. Metering systems are used to provide
measurement information in fluid transport, petroleum and chemical processing, custody
transfer of liquids, blending systems, in product batching and in field or plant operations.
• Each turbine meter is comprised of a cylindrical housing that contains a precise turbine
rotor assembly. The magnetic pickoffs are mounted in a boss on the turbine meter
body.
• As fluid passes through the turbine meter, it causes the rotor to revolve with an angular
velocity proportional to flow.
• The rotor blades or rim buttons passing through the magnetic field of the pickoff
generate a pulsing voltage in the coil of the pickoff assembly. Each voltage pulse
represents a discrete volume. The total number of pulses collected over a period of
time represents the total volume metered.
• The sinusoidal signal from each pickoff has a low amplitude and is not normally relied
upon for transmission distances over 6 meters (20 feet). The signal must, therefore, be
amplified. This is achieved with a preamplifier contained within the LME that is
mounted on the turbine meter.
• These pulse signals are typically transmitted to control room instrumentation, such as
flow computers, and may also be required to transmit to prover computers which
calculate, display, transmit, control or record the flow sensed by the rotor. The results
may be displayed as pulse-counts or standard engineering units, such as gallons, liters,
barrels, etc.
Introduction User manual
March 2019 P/N 3-9008-515
14 Daniel Series 1500 Liquid Turbine Meter, NPS 3-24