Pulsar blackbox 130, Инструкция по эксплуатации

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Example 2 Alternating Control (pump down)
A sump is typically used to temporarily hold water or effluent, and when the
level reaches a specific point, the sump is pumped down, with the fluid being
transferred to another process.
empty distance (P105), 15.0 feet
100%, span (P106), 13.5 feet
(output = 20mA)
pump 1+2 off (P214, 224), 1.5 feet
0% , empty level (output = 4mA)
pump 2 on (P 223), 6.0 feet
pump 1 on (P 213), 4.0 feet
In this example a
blackbox
with dB6 is being used to control pumps on a
pump down application, there are two pumps, and the duty pump is to be
alternated between the pumps.
This will operate as follows. During normal operation, pump 1 will come on
at 4.0 feet, and pump down to 1.5 feet. The setpoints are then shifted to pump
2 , which will come on first next time.
During peak periods, when pump 1 cannot cope, pump 1 will come on at 4.0
feet, pump 2 will come on at 6.0 feet, and pump down to 1.5 feet. The
setpoints are then shifted to pump 2 , which will come on first next time .
The 4 to 20mA output will be representative of level.