Rosemount 1199, Справочное руководство

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Reference Manual
00809-0100-4002, Rev BB
November 2012
Rosemount 1199
4-2
Zero-based lower range
value
Figure 4-1.
L
min
= the minimum level of process and typically the 4mA lower range value
L
max
= the maximum level of process and typically the 20mA upper range
value
Atm = Atmospheric pressure (vented tank)
SG = Specific gravity of the process
Sg = Specific gravity of the remote fill fluid
Tank span = L
max
x SG
Tank Span: (108 in. x 0.75) = 81 inH
2
O
4 mA = L
min
x SG + Hd x Sg
(0 x 0.75) + (0 in x 0.934)= 0 inH
2
O
4mA = 0 inH
2
O
20 mA = L
min
x SG + Hd x 0.934
(108in x 0.75) + (0)= 81 inH
2
O
20mA = 81 inH
2
O
NOTE
Both installations would have the same calculated range points.
NOTE
Silicone 200 has a specific gravity of 0.934.
Remote capillary
Direct mount