Emerson 3051N User Manual

Page of 100
Reference Manual
00809-0100-4808, Rev CA
June 2008
Rosemount 3051N
2-14
Smart transmitters operate differently than analog transmitters. A smart 
transmitter uses a microprocessor and sensor memory that contains 
information about the sensor’s specific characteristics in response to pressure 
and temperature inputs. A smart transmitter compensates for these sensor 
variations. The process of generating the sensor performance profile is called 
factory characterization. Factory characterization also provides the ability to 
readjust the 4 and 20 mA points without applying pressure to the transmitter.
The trim and rerange functions also differ. Reranging sets the transmitter 
analog output to the selected upper and lower range points and can be done 
with or without an applied pressure. Reranging does not change the factory 
characterization curve stored in the microprocessor. Sensor trimming requires 
an accurate pressure input and adds additional compensation that adjusts the 
position of the factory characterization curve to optimize transmitter 
performance over a specific pressure range.
NOTE
Sensor trimming adjusts the position of the factory characterization curve. It is 
possible to degrade the performance of the transmitter if the sensor trim is 
done improperly or with inaccurate equipment. Contact Rosemount Nuclear 
Instruments, Inc. at 952-949-5210 if you have questions.
Table 2-2.  Recommended
Calibration Tasks.
Transmitter
Bench Calibration Tasks
Field Calibration Tasks
3051ND
3051NG
1.
Set output configuration parameters:
a.
Set the process variable units.
b.
Set the output type.
c.
Set the range points.
d.
Set the damping value.
2.
Optional: Perform a full sensor trim. (Accurate 
multimeter required.)
3.
Optional: Perform an analog output trim. (Accurate 
multimeter required.)
1.
Reconfigure parameters if necessary.
2.
Zero trim the transmitter to compensate for mounting 
effects or static pressure effects.
3051NA
1.
Set output configuration parameters:
a.
Set the process variable units.
b.
Set the output type.
c.
Set the range points.
d.
Set the damping value.
2.
Optional: Perform a full sensor trim if equipment 
available (accurate absolute pressure source 
required), otherwise perform the low trim value section 
of the full sensor trim procedure.
3.
Optional: Perform an analog output trim (accurate 
multimeter required).
1.
Reconfigure parameters if necessary.
2.
Perform low trim value section of the full sensor trim 
procedure to correct for mounting position effects.
Notes:
A HART Communicator is required for all sensor and output trim procedures.
Rosemount 3051N Range 4 and Range 5 transmitters require a special calibration procedure when used 
in differential pressure applications under high static line pressure (see “Compensating Rosemount 3051N 
Range 4 and 5 Differential Transmitters for Line Pressure” on page 2-20).