Emerson Rosemount 3051SAL Reference Manual page 63

Reference Manual
00809-0200-4802, Rev BA
For line pressures above 2000 psi (138 bar), the zero effect error is ± 0.2% of the upper range
limit plus an additional ± 0.2% of upper range limit error for each 1000 psi (69 bar) of line
pressure above 2000 psi (138 bar).
Example: Line pressure is 3000 psi (3 kpsi). Zero effect error calculation:
± {0.2 + 0.2 x [3 kpsi - 2 kpsi]} = ± 0.4% of the upper range limit
Span effect:
Correctable to ±0.2% of reading per 1000 psi (69 bar) for line pressures from 0 to 3626 psi (0 to
250 bar)
The systematic span shift caused by the application of static line pressure is -1.00% of reading
per 1000 psi (69 bar) for Range 4 transmitters, and -1.25% of reading per 1000 psi (69 bar) for
Range 5 transmitters.
Use the following example to compute corrected input values.
Example
A transmitter with model number 3051S_CD4 will be used in a differential pressure application
where the static line pressure is 1200 psi (83 bar). The transmitter output is ranged with 4 mA at
500 inH
To correct for systematic error caused by high static line pressure, first use the following
formulas to determine corrected values for the low trim and high trim.
LT = LRV + S x (LRV) x P
Where:
HT = URV + S x (URV) x P
Where:
In this example:
To calculate the low trim (LT) value:
Operation and Maintenance
O (1,2 bar) and 20 mA at 1500 inH
2
LT =
LRV =
S =
P =
HT =
URV =
S =
P =
URV =
LRV =
P =
S =
LT =
Section 5: Operation and Maintenance
O (3,7 bar).
2
Corrected Low Trim Value
Lower Range Value
–(Span shift per specification)
Static Line Pressure
Corrected High Trim Value
Upper Range Value
–(Span shift per specification)
Static Line Pressure
1500 inH O (3.74 bar)
2
500 inH O (1.25 bar)
2
1200 psi (82.74 bar)
± 0.01/1000
500 + (0.01/1000)(500)(1200)
May 2013
55