Transmitter Overview - Emerson Rosemount 3051P Reference Manual

Reference Manual
00809-0700-4001
2.4

Transmitter overview

The Rosemount 3051P In-Line Pressure Transmitter is offered for gage pressure (GP) and
absolute pressure (AP) measurements. The transmitter uses piezoresistive sensor
technology for AP and GP measurements.
The major components of the transmitter are the sensor module and the electronics
housing. The sensor module contains the oil-filled sensor system (isolating diaphragm, oil
fill system, and sensor). The electronics board is located within the electronics housing.
The electrical signals from the sensor module are transmitted to the electronics board
which contains the memory module and the analog to digital signal converter (A/D
converter). The signal is then converted to a 4–20mA analog output signal or HART
digital signal. The electronics housing contains the output electronics board, the optional
external configuration buttons, and the terminal block. The basic block diagram of the
transmitter is illustrated in
When pressure is applied to the isolating diaphragm, the oil deflects the sensor, which
then changes its capacitance or voltage signal. This signal is then changed to a digital
signal by the Signal Processing. The microprocessor then takes the signals from the Signal
Processing and calculates the correct output of the transmitter. This signal is then sent to
the D/A converter, which converts the signal back to the analog signal and then
superimposes the HART signal on the 4–20 mA output.
An optional LCD display can be ordered that connects directly to the interface board,
which maintains direct access to the signal terminals. The display indicates output and
abbreviated diagnostic messages. A glass display cover is provided. For 4-20 mA HART
output, the LCD display features a two-line display. The first line displays the actual
measured value; the second line of six characters displays the engineering units. The LCD
display can also display diagnostic messages.
Note
LCD display uses a 5x6 character display and can display output and diagnostic messages.
The local operator interface (LOI) display uses an 8x6 character display and can display
output and diagnostic messages as well as and LOI menu screens. The LOI display comes
with two buttons mounted on the front of the display board. See
Rosemount 3051P
Figure 2-2.
Configuration
April 2020
®
Figure 2-1.
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