Bailey Platinum standard Series, Инструкция по эксплуатации

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DESCRIPTION AND OPERATION
FUNCTIONAL OPERATION
WBPEEUI110505A0 2 - 9
1. Calculate the empty tank pressure as the primary lower range value. Since
the cell is below the bottom of the sphere by 12 in., the primary lower range
value is equal to 12 in. H
2
O.
2. Calculate the primary upper range value. The full pressure is equal to
150 in. H
2
O, but since the zero offset of 12 in. H
2
O was calculated as the pri-
mary lower range value, the primary upper range value must be equal to 150
plus 12, or 162 in. H
2
O.
3. The secondary lower range value is the empty volume of the tank (always
zero).
4. The full volume of the tank is calculated to be 7,650 gallons for the sec-
ondary upper range value.
FLAT END (CYLINDRICAL) TANK VOLUME CALCULATION
Figure 2-8 shows a flat end (cylindrical) tank setup. This is a
general purpose tank. This procedure shows how to calculate
the values entered into the transmitter (via the Type STT ter-
minal) during configuration if
VOL./TANK is chosen from the
OUTPUT TYPE menu.
1. The empty tank pressure is the primary lower range value.
a. If the location of the cell is at the bottom of the tank,
then the primary lower range value is 0.00 kilopascals
(0.00 inches of water).
b. If the location of the cell is below the bottom of the
tank, as shown in Figure
2-8 , then offset the zero by set-
ting the primary lower range value to the pressure corre-
sponding to the distance between the bottom of the tank
and the cell times the specific gravity of the liquid.
2. The full tank pressure is the primary upper range value.
a. If the location of the cell is at the bottom of the tank,
then the primary upper range value is the height of the
tank times the specific gravity of the liquid.
b. If the location of the cell is below the bottom of the
tank, as shown in Figure
2-8 , then the primary upper
range value is the height of the tank times the specific
gravity of the liquid plus the lower range value.
NOTE: From Steps 1 and 2, it can be seen that whether the cell is at
or below the bottom of the tank, the span between the lower range
value and upper range value is the same.
volume of sphere
4
π
r
3
3
----------- in.
3
and =
volume at any height (h) in tank
1
3
---
π
h
2
3 r h –
( )
in.
3
=
in.
3
0.004329
×
gallons =