Emerson Rosemount 3051 Reference Manual page 64

Section 3: Configuration
November 2012
Note
Transmitters are shipped from Emerson Process Management fully calibrated per request or by
the factory default of full scale (zero to upper range limit).
Note
Regardless of the range points, the 3051 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
transmitter detects a pressure of 25 inH
of range reading.
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.



Note
If the transmitter security switch is ON, adjustments to the zero and span will not be able to be
made. Refer to
Rerange with a Field Communicator or AMS Device Manager Only.
The easiest and most popular way to rerange is to use the Field Communicator only. This
method changes the range values of the analog 4 and 20 mA points (1 and 5 Vdc points)
independently without a pressure input. This means that when you change either the 4 or 20
mA setting, you also change the span.
An example for the 4-20 mA HART output:
If the transmitter is ranged so that
4 mA = 0 inH
20 mA = 100 inH
and you change the 4 mA setting to 50 inH
are:
4 mA = 50 inH
20 mA = 100 inH
Note that the span was also changed from 100 inH
remained at 100 inH
To obtain reverse output, simply set the 4 mA point at a greater numerical value than the 20 mA
point. Using the above example, setting the 4 mA point at 100 inH
inH O will result in reverse output.
2
54
Rerange with a Field Communicator or AMS Device Manager only.
Rerange with a pressure input source and a Field Communicator or AMS Device
Manager.
Rerange with a pressure input source and the local zero and span buttons (option D4).
"Configure security and alarm" on page 20
O, and
2
O,
2
O, and
2
O.
2
O.
2
O, it digitally outputs the 25 inH
2
for security information.
O using the communicator only, the new settings
2
O to 50 inH O, while the 20 mA setpoint
2 2
Reference Manual
00809-0100-4001, Rev JA
O, and the
2
O reading and a 250%
2
O and the 20 mA point at 0
2
Configuration