INSTALLATION
SETUP AND PHYSICAL INSTALLATION
3 - 8
WBPEEUI110505A0
OPEN TANK LEVEL MEASUREMENT
In an open vessel, level can be measured by making a pressure
measurement (P) at the bottom of the vessel (Fig.
). The
pressure at the transmitter high pressure
(+) connection is
equal to the product of the height (h
2
) and the specific gravity
(SG) of the liquid. Since SG is known, and P is the measured
pressure, then:
1. The transmitter design allows for direct connection of the
high pressure
(+) side of the cell to the tank or vessel.
Figure 3-5. Closed Tank (Noncondensing Atmosphere) Level
Measurement
h
2
P
SG
---------
=
D RY L E G
H IG H E S T L E V E L
TO B E M E A S U R E D
L O W E S T LE V E L
TO B E M E A S U R E D
+
–
h
2
h
1
T 0 2 2 3 3 A
2 0
1 5
1 0
5
0
-250
(-62 .2)
D IF F E R E N T IA L P R E S S U R E
IN . H O (kPa )
2
+ 2 50
(+ 62.2 )
4
S PA N = (h – h ) x S G
2
1
Z E RO
S U P P R E S S IO N
= h x S G
1
O U T P U T
IN m A
Содержание Platinum standard Series
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