Emerson 3051N User Manual

Page of 100
Reference Manual 
00809-0100-4808, Rev CA
June 2008
2-21
Rosemount 3051N
HT
c
 = URV + S (URV) P
s
 
In this example:
 
To calculate the corrected low trim (LT
c
) value:
 
To calculate the corrected high trim (HT
c
) value:
 
To complete a Rosemount 3051N full trim, enter the corrected values for low 
trim (LT) and high trim (HT). Refer to “Full Trim” on page 2-18.
Enter the corrected input values for low trim and high trim through the 
communicator keypad after you apply the nominal value of pressure as the 
transmitter input.
NOTE
After calibrating Rosemount 3051N Range 4 and Range 5 transmitters for 
high differential pressure applications, rerange the 4 and 20 mA points using 
the communicator to maintain the systematic static line pressure correction. 
You may re-zero the 4 mA point at line pressure after installation using the 
local zero button without affecting the completed calibration.
Where:
HT
c
 =
Corrected High Trim Value
URV =
Upper Range Value
S =
–(Span shift per specification)
P
s
 =
Static Line Pressure
URV =
1500 inH
2
O
LRV =
500 inH
2
O
P
s
 
=
1200 psi
S =
-(-0.01/1000 psi) = 0.01/1000psi
LT
c
 
=
500  in  H
2
0 + (0.01/1000 psi)(500 in H
2
0)(1200 psi)
LT
c
 
=
506 in  H
2
O
HT
c
 
=
1500  in  H
2
0 + (0.01/1000 psi)(1500 in H
2
0)(1200 psi)
HT
c
 
=
1518  in  H
2
O