Siemens SITRANS P500, Operating Instructions Manual, Page: 43 / 238

Install
4.6 "Level" installation
SITRANS P500 with HART
Operating Instructions, 12/2014, A5E02344528-09
43
4.6.3.2 Measurement in a closed container
When taking measurements in a closed container without or with little condensation
formation, the negative pressure line is not filled.
Formula:
Start of scale value
Δp
MA
= ρ · g · h
U
Full scale value
Δp
ME
= ρ · g · h
O
h
U
Start of scale value Δp
MA
Start of scale value to be adjusted
h
O
Full scale value Δp
ME
Full scale value to be adjusted
p Pressure ρ Density of the measured medium in
the container
g Acceleration due to gravity
Measurement assembly on a closed container:
no or little condensation separation
When taking measurements in a closed container with strong condensation formation, you
must fill the negative pressure line (mostly with the condensation of the measured medium)
and install a condensation pot.
For measurement on open vessels there is no need to connect the minus pipework, since
the minus side is open to the atmosphere.