Siemens P technical specifications Measuring setups without remote seals, 185

© Siemens AG 2008

SITRANS P measuring instruments for pressure

	Remote seals
	Measuring setups without remote seals
	Also you must make sure that the level in the container is al-
■Overview
	ways above the top spigot.
Notes	• When measuring density, make sure that the level of the me-
• For the separation layer measurement, the separation layer	dium remains constant. The level should be above the top
	spigot
has to be positioned between the two spigots.		2
■Dimensional drawings
Pressure transmitters for differential pressure, for flanging
Measuring setups for open containers

Full-scale value

H o		r
		Start-of-scale value
	H u

+

		Constant level
		= full-scale value
		r2
		Separation layer
H	o	r1
		Start-of-scale value

Hu

+

Level measurement

Start-of-scale:	pMA = r · g · HU
Full-scale:	pME = r · g · HO
Legend
pMA	Start-of-scale value to be set
pME	Full-scale value to be set

rDensity of medium in vessel

gLocal acceleration due to gravity

HU	Start-of-scale value
HO	Full-scale value

Separation layer measurement

Start-of-scale: pMA = g · (HU · r1 + (HO - HU) · r2)

Full-scale:	pME = r1 · g · HO
Legend
pMA	Start-of-scale value to be set
pME	Full-scale value to be set
r1	Density of heavier liquid
r2	Density of lighter liquid

gLocal acceleration due to gravity

HU	Start-of-scale value
HO	Full-scale value

Ho

Constant level

r

Density measurement

Start-of-scale: pMA = rMIN · g · HO

Full-scale:	pME = rMAX · g · HO
Legende
pMA	Start-of-scale value to be set
pME	Full-scale value to be set
rMIN	Minimum density of medium in vessel
rMAX	Maximum density of medium in vessel

gLocal acceleration due to gravity

HO Full-scale value in m

+

Siemens FI 01 · 2009

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