Xylem hydrovar, Installation, Operation And Maintenance Manual

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Graph
Position numbers
2
H
Q
1
f = 100 %
1. The pressure at zero demand (all valves closed).
2. The pressure plus lift amount to compensate the friction loss.
11.4 Example: P500 SUBMENU SEQUENCE CNTR.
Graph
Calculation process for the sequence centre value
1. Lead pump reaches its P515 ENABLE FRQ.
2. Actual value falls to the cut in-value of the 1
st
assist pump. The 1
st
assist pump switches
on automatically. (Cut in-value = P02 REQUIRED VAL - P510 ACT.VAL.DEC)
3. A new required value, P03 EFF.REQ.VAL is calculated after the start up. P03
EFF.REQ.VAL = P02 REQUIRED VAL - P510 ACT.VAL.DEC + P505 ACT.VAL.INC
Calculations of the new required value for multi pump applications
k.... number of active pumps (k > 1)
11 Technical Reference
104 HVL 2.015-4.220 Installation, Operation, and Maintenance Manual