Xylem IM098 AQUAVAR Model 56 Controller - Manual (Page 37)

Operator Custom Features and Displays
Lift Value Adjustable between 0 to the
pre-selected NORMALIZE. Application
Example: 1) Pump 1 reaches f
max
(maximum
speed, 2) Pressure falls and reaches the
start-value of the 2nd pump (= REQUIRED
VALUE - ACTU. VALUE DEC.), 3) Pump 2 is
switched on automatically, 4) The required
value is calculated after the start of the 2nd
pump in the following way.
New required value = REQUIRED VALUE –
ACTU. VALUE DEC. + ACU. VALUE INC.
GENERAL
1) If Actual Value Increase equals Actual Value Decrease the pressure stays constant throughout
flow range.
2) If Actual Value Increase is greater than Actual Value Decrease, the pressure rises as
the lag pumps turn on and the flow increases.
3) If Actual Value Increase is less than the Actual Value Decrease, the pressure drops as the lag
pumps turn on and the flow increases.
Fall Value For scaling the set pressure of
pumps 1 to 4. Adjustable from 0.0 to 100%
determines the start-value of the 2
nd pump and
the other following pumps. (start value =
REQUIRED VALUE - ACT. VALUE DEC.)
32
ACTU. VALUE INC.
5 PSI
H
Q
7
6
5
4
3
2
1
0
PUMP 1 PUMP 1 +
PUMP 2 PUMP 1 +
PUMP 2 +
PUMP 3
2
1
3
ACTU
AL V
A
LUE DECREASE
ACTU
AL
VA
LU
E
INCREASE
Diagram 12
ACTU. VALUE DEC.
4 PSI