Xylem IM043 AQUAVAR Variable Speed Pump Control - Manual (Page 59)

Regulation Mode
The “ Normal” setting increases the output speed with falling signal (constant pressure in dis-
charge). The “ Inverse” setting decreases the output speed with falling signals (suction control).
Submenu Sequence Control - for further information see Section V
Use this menu to allow starting and stopping of up to 4 pumps with the RS-485 communication
port. The following setup items allow the user to determine when the pumps will start and stop.
Actual value Increase
Enter a value to increase the setpoint (required value) after a lag pump starts. Initiates a pressure
boost, when the second pump starts. Pressure loss compensation for multi-pump.
Actual value Decrease
Enter a value to decrease the setpoint (required value) after a lag pump starts. The required value
will be calculated from the following equation after a lag pump starts:
NEW REQUIRED VALUE = REQUIRED VALUE - ACT. VALUE DEC. + ACT. VALUE INC.
This setting will allow a system pressure drop, before starting second pump in multi-pump
systems. For no modification to the setpoint keep both of the increase and decrease values at the
same value.
Actual value decrease pressure setting and maximum frequency of pump must be achieved before
second pump will start in a multi-pump system.
Enable Sequence Control
Enter the maximum speed prior to starting the lag pump(s). Typically set a +2 HZ below the
maximum frequency. To disable pump staging set this value greater than the maximum frequency.
This should be set for your maximum frequency of each pump or below.
Switch Interval
Enter the amount of time the lead pump should operate prior to alternating the pump sequence.
This variable allows equal wear on all controlled pumps. Set this value greater than 100 hours to
deactivate alternation.
Source Required value
Used to set the address for the source of a second required value. May be set to off, ADR1, ADR2,
ADR3 or ADR4. Default is off.
Submenu Synchronous Control
To use this method of multiple pump control, all pumps must be exactly the same. When the syn-
chronous control is active all of the activated pumps work together to satisfy the required value.
When the synchronous control is deactivated the lead pump(s) run at full speed while the lag
pump modulates in speed to satisfy the required value.
Operator Custom Features and Displays
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