Pulsar ULTRA 5, Instruction Manual

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Example 2 Level Monitoring and Control (up or down)
A vessel, containing a liquid that has a variation in level that is to be
monitored, and when the level reaches a specific point, the vessel is pumped
down, with the fluid being transferred to another process. The pump will be
assigned to Relay 1 a High Alarm to Relay 2 and Low Alarm to Relay 5.
empty distance (P105), 3.5m
100%, span (P106), 2.8m
85%, high alarm on (P223), 2.38m
80%, high alarm off (P224), 2.24m
80%, control (down) on (P213), 2.24m
15% , low alarm off (P254), 0.42m
10%, low alarm on (P253), 0.28m
0%, empty level
20%, control (down) off (P214), 0.7m
In this example, there is a pump (relay 1), which will come on if the level
rises to 2.24 m, and go off when the level drops to 0.7 m. (
control down ). If
the level rises to 2.4 m, then the high-level alarm (relay 2) will come on
until the level drops to 2.24 m. If the level falls to 0.28m, then the low-level
alarm (relay 5) will come on until the level rises to 0.42 m.
Alternatively, if it is a control up application, then the on and off points for
the control relay are reversed, so the control relay comes on when the level
is at 0.7 m and goes off when it rises to 2.24 m.
The display will show the level in the tank and the mA output will be
representative of level where 4mA = empty level (0%) and 20mA = 2.8m
(100%).