Emerson Rosemount 2051 Wireless Series, Reference Manual, Page: 127 / 250

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Reference Manual
00809-0100-4100, Rev AA
Section 1: Introduction
June 2012
Introduction
1.4 Transmitter overview
The Rosemount 3051C Coplanar design is offered for Differential Pressure (DP), Gage Pressure
(GP) and Absolute Pressure (AP) measurements. The Rosemount 3051C utilizes capacitance
sensor technology for DP and GP measurements. The Rosemount 3051T and 3051CA utilize
piezoresistive sensor technology for AP and GP measurements.
The major components of the Rosemount 3051 Wireless transmitter are the sensor module and
the electronics housing. The sensor module contains the oil filled sensor system (isolating
diaphragms, oil fill system, and sensor) and the sensor electronics. The sensor electronics are
installed within the sensor module and include a temperature sensor, a memory module, and
the analog to digital signal converter (A/D converter). The electrical signals from the sensor
module are transmitted to the output electronics in the electronics housing. The electronics
housing contains the output electronics board, the wireless antenna, and the battery. The basic
block diagram of the Rosemount 3051CD Wireless device is illustrated in
Figure X-X on page X .
For the Rosemount 3051, pressure is applied to the isolating diaphragm(s). 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 via
wireless communication to the Gateway.
An optional LCD 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 WirelessHART 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 can also display diagnostics messages.
Note
LCD Display utilizes a 5x6 character display and can display output and diagnostic messages. See
Figure 1-2 .
Figure 1-2. LCD/LOI Display
LCD Display