Emerson Rosemount 2051 Reference Manual page 49

Reference Manual
00809-0100-4101
3.7.3 Rerange
The range values command sets each of the lower and upper range analog values
(4 and 20 mA points and 1 and 5 Vdc points) to a pressure. The lower range point
represents 0% of range and the upper range point represents 100% of range. In practice,
the transmitter range values may be changed as often as necessary to reflect changing
process requirements. For a complete listing of range and sensor limits, refer to
Sensor
Note
Transmitters are shipped from Emerson fully calibrated per request or by the factory
default of full scale (zero to upper range limit).
Note
Regardless of the range points, Rosemount 2051 will measure and report all readings
within the digital limits of the sensor. For example, if the 4 and 20 mA points are set to
0 and 10 inH
25 inH
Select from one of the methods below to rerange the transmitter. Each method is unique;
examine all options closely before deciding which method works best for your process.
Reference Manual
Figure 3-3: 4–20 mA HART Square Root Output Transition Point
A. Full scale output (mA dc)
B. Full scale flow (%)
C. Sq. root curve
D. Transition point
E. Slope = 42
F. Slope = 1
G. Sq. root curve
H. Transition point
I. Linear section
Note
For a flow turndown of greater than 10:1, it is not recommended to perform
a square root extraction in the transmitter. Instead, perform the square root
extraction in the system.
Limits.
O, and the transmitter detects a pressure of 25 inH
2
O reading and a 250 percent of range reading.
2
Configuration
March 2024
Range and
O, it digitally outputs the
2
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