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Example 2 Alternating Control (pump down)
Example 2 Alternating Control (pump down)
Example 2 Alternating Control (pump down)
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), 5.0m
100%, span (P106), 4.7m
(output = 5VDC)
pump 1+ 2 off (P214, 224), 0.5m
0% , empty level (output = 0VDC)
pump 2 on (P 223), 1.4m
pump 1 on (P 213), 1.0m
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 0.8 m, and pump down to 0.5 m. 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
1.0m,
pump 2
will come on at 1.4 m, and pump down to 0.5 m. The
setpoints are then shifted to
pump 2
, which will come on
first next time
.
The 0 to 5VDC output will be representative of level.
