Xylem IM167 R8 Aquavar CPC (Centrifugal Pump Control) - Manual (Page 110)

110
Parameter Value Notes
16.01 DI4 A switch would be wired into DI4 and the DCOM on the X1 terminal to
toggle between set point 1 and set point 2.
16.02 KEYPAD The setpoint would be manually entered using the Aquavar keypad.
When the switch [DI4] is set to “0” (Open), the set point would be entered
as “110 psi” using the keypad “REF” button.
16.03 KEYPAD The set point would be manually entered using the Aquavar keypad.
When the switch [DI4] is set to “1” (Closed), the set point would be entered
as “60 psi” using the keypad “REF” button.
WARNING! Parameter 16.01, 16.02 and 16.05 can only be changed when the motor
is not running. Most parameters require you to stop the pump, before programming.
System Curve Compensation
The AQUAVAR CPC system can automatically compensate for system friction losses due to
increased flow in single pump operation or multi-pump backup modes. Tables are available in
most pump catalogs to assist in determining the amount of friction loss that can be expected
for various pipe sizes and flow rates on simple systems. As flow increases, velocity increases
causing friction loss through piping and various fixtures. Normally this would provide a loss in
flow or overall pressure to the system. With the Aquavar you can compensate for this friction
loss!
The diagram below illustrates a typical system curve in relation to pump speed.
In this case the system pressure set point is shown at shutoff ( 0 flow) and the increase in
setpoint pressure is shown for increasing flow. EXAMPLE - If the set point is 150 Ft [65 PSIG
@ 1.0 SG] and the system resistance increase 10 Ft at the maximum flow rate, or roughly 7%
of the set point, parameter 21.08 would be set as “7”.
FEATURES
Constant Pressure Line
Pr
essur
e Incr
ease
Resulting S
ystem Curve C
ompensation
System Curve
Set
Pressure
Head /
Pressure
Flow
N=100%
%N
%N
%N
%N
0