Pressure Transducer Block; Execution; Figure 3: Pressure Transducer Block - Honeywell ST700 User Manual

3.4

Pressure Transducer block

The Pressure Transducer block is used to sense and display pressure. It contains details of
the primary process variable, secondary process variables, tertiary variables, and quaternary
variables. The primary measurement is differential, absolute or gauge pressure. For
example, in a Differential Pressure transmitter, meter body temperature is the secondary
variable and static pressure the tertiary variable. In addition, it can measure onboard
electronics temperature.

Execution

The block has firmware revision parameter that indicates the revision of the sensor module
that is the firmware revision details. The primary measurement is represented by
PRIMARY_VALUE_TYPE parameter. The sensor provides more than one pressure
measurement type, such as Differential pressure/Gauge pressure/Absolute pressure and
Static pressure. The block computes its output using primary sensor data and parameters.
The calculation is modeled as shown in Figure 3.
The Transducer block supports the following process variables:
•
Primary Value – DP/GP/ AP
•
Secondary Value – Meterbody temperature
•
Tertiary Value – Static pressure is applicable only for DP
•
Quaternary Value – Fluid level
•
Electronic Housing temperature
Revision 2.0 FOUNDATION Fieldbus ST 700 Pressure Transmitter User's Guide

Figure 3: Pressure Transducer Block

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