Emerson Rosemount 2151N Reference Manual page 44

Rosemount 2151N
Figure 3-10 – High Static Line
Pressure Span Correction using
Method 2; Example 1
Figure 3-10a – Example 1 for High Static Line
Pressure Span Correction using Method 2
(English Units)
35
Figures 3-10 and 3-11 outline two examples of calculating a
High Static Line Pressure Span Correction using Method 2.
"Example 1" in Figure 3-10 contains a calculation for a Zero
Based Calibration Range. Figure 3-10a uses English units
(psi) for the calculation while Figure 3-10b uses SI units
(MPa)
"Example 2" in Figure 3-11 demonstrates the calculation for a
Zero Elevated Calibration Range. "Example 2" can also be
followed for Zero Suppressed Calibration Ranges. Figure 3-
11a uses English units (psi) while Figure 3-11b uses SI units
(MPa).
Range 4 for a calibration of 0 to 45 psi corrected for 1,500
psi static line pressure
1. In this example LRV is 0 psid. Zero differential
pressure points require no span correction.
2. Calculate the corrected URV pressure input
= 45 psi – ((0.01 X 45 psi) X (1500 psi/1000 psi))
= 44.325 psi
3. At atmospheric static line pressure, with zero
differential pressure applied, adjust the zero until the
transmitter output reads 4 mA.
4. Remaining at atmospheric static line pressure, apply
44.325 psi to the high side process connection and
adjust the span until the transmitter output reads 20
mA.
5. Check to assure desired outputs are achieved and
repeat steps 3 and 4 if necessary.
When the transmitter is exposed to 1,500 psi static line
pressure, within specified uncertainties, the output will be 4
mA at 0 psi and 20 mA at 45 psi.
Reference Manual
00809-0000-4851 Rev AD
December 2023
Calibration