PULSAR MEASUREMENT
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Example 3 Volume Application
A cylindrical tank with a diameter of 2m and a flat base that is typically used
to temporarily hold liquid, and you wish to know the volume of liquid. You
also require a high and low alarm and when the level reaches a specific
point, the vessel is pumped down, with the fluid being transferred to
another process.
The application is to be assigned to Point 1 (Transducer 1)
In this example, there is a control down relay (relay 1), which will come on if
the level rises to 8.0 feet, and go off when the level drops to 2.0 feet.
(
control down
). If the level rises to 8.5 feet, then the high-level alarm (relay
4) will come on until the level drops to 8.0 feet. If the level falls to 1.0 feet,
then the low-level alarm (relay 5) will come on until the level rises to 1.5 feet.
The display will show the volume of fluid in the tank and the mA output will
be representative of Volume where 4mA = empty (0%) and 20mA = Max
Volume (100%).
Empty Distance (P105), 11.0 feet
100%. Span (P106), 10.0 feet
85%. High alarm on (P213), 8.5 feet
80%. High alarm off (P214), 8.0 feet
0%, Empty level
10%. Low alarm on (P233), 1.0 feet
15%, Low alarm off (P234), 1.5 feet
80%. Control (down) on (P213), 8.0 feet
20%. Control (down) off (P214), 2.0 feet
