Emerson manual Rosemount 3051S, Reference Manual

Reference Manual

00809-0200-4801, Rev BA April 2007

Rosemount 3051S

Solution to situation #3

Table 3-4. Analog Input function block configuration for a pressure transmitter used in level measurement (Situation #3).

Table 3-4 lists the appropriate configuration settings.

Parameter	Configured Values
L_TYPE	Indirect
XD_SCALE	2 to 9 psi
OUT_SCALE	0 to 16 ft
Channel	1 - pressure

In this example, when the PV is 4 psi, OUT will be calculated as follows:

OUT = 4 psi – 2 psi * (16 ft. – 0 ft.) + 0 ft. = 4.57 ft. 9 psi – 2 psi

Differential pressure transmitter to measure flow

Table 3-5. Analog Input Function Block Configuration for a Differential Pressure Transmitter.

Situation #4

The liquid flow in a line is to be measured using the differential pressure across an orifice plate in the line. Based on the orifice specification sheet, the differential pressure transmitter was calibrated for 0 to 20 inH20 for a flow of 0 to 800 gal/min.

Solution

Table 3-5 lists the appropriate configuration settings.

Parameter		Configured Values
L_TYPE		Indirect Square Root
XD_SCALE		0 to 20 in.H2O
OUT_SCALE		0 to 800 gal/min.
Channel		1 - pressure
Out =	PV------------------------------------------------–XDSCALE0(OUTSCALE100 – OUTSCALE0) + OUTSCALE0
	XDSCALE100
OUT=	8inH2O – 0inH2O
	20inH-----------------------------------------------------2O– 0inH2O (800gal/min. - 0gal/min.) + 0gal/min. = 505.96gal/min.

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