Xylem HYDROVAR Smart - Manual (Page 30)

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7.21 Submenu Sequence control
S U B M E N U
Seq. Control
Programming of the Multipump Operation:
Up to four pumps can be connected using the integrated RS-485 interface, by connecting
the terminals /1, /2 and /3 of the terminal blocks X5 or X6 of each pump together).
However, the following additional programming must be carried out in the submenu:
Press ¾ for about 3 seconds to enter the submenu and the display changes to
7.21.1 Lift Value
ACTU. VALUE INC.
0.35 Bar
Adjustable between 0.0 to the pre-selected
Sensor range
Operation of the start of the slave pump:
1) Pump 1 reaches ENABLE SEQ. CONTROL (maximum speed)
2) Pressure falls and reaches the start-value of the 2
nd pump
(= REQUIRED VALUE – ACTU. VALUE DEC.)
3) Pump 2 is switched on automatically
4) The required value is calculated new, after the start of the 2
nd pump in the
following way!
New required value = REQUIRED VALUE – ACTU. VALUE DEC. + ACU. VALUE INC.
Generally:
k ... Number of active pumps (k >1)
p = p
set
+ (k-1)*[lift value – fall value]
• Lift value = Fall value ⇒ Pressure constant when pumps switch on
• Lift value > Fall value ⇒ Pressure rises when lag-pump switches on
• Lift value < Fall value ⇒ Pressure falls when lag-pump switches on