ABB Platinum standard Series, Инструкция по эксплуатации

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INSTALLATION
SETUP AND PHYSICAL INSTALLATION
3 - 12 WBPEEUI110504A0
tion purposes by a positive pressure, increasing in value,
imposed on the - (low pressure) connection of the cell.
1. Refer to Figure 3-9 for a typical piping arrangement for
closed tank level measurements in condensing atmospheres.
2. Make the connection from the lower tap of the tank to the +
(high pressure) side of the transmitter.
3. Make the connection from the upper tap of the tank to the
- (low pressure) side of the transmitter.
4. Observe the conventions outlined in Figure 3-10 .
5. The output of the transmitter is proportional to the level of
the liquid above the cell times the specific gravity of the liquid.
If the zero point of the desired level range is above the cell, the
lower range value must be changed to reflect this. Refer to
Section 4 and Section 5 for more information. Figure 3-9
includes a graphical representation of this application.
Figure 3-7. Closed Tank, Noncondensing
Atmosphere Level Measurement
T022 21A
D RY L E G L IN E
2 0
1 5
1 0
5
0
-25 0
(-6 2 .2 )
D IF F E R E N T IA L P R E S S U R E
IN . H O (k Pa)
2
O U T P U T m A
+2 50
(+62 .2)
4
S PA N = (h – h ) x S G
2 1
ZE RO
S U P P R E S S IO N
= h x S G
1
+ –
h
2
h
1
M A X
L E V E L
TO B E
M E A S U R E D