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7.2 Pump control
During operation, the pump head will be controlled according to the
principle "proportional-pressure control" (PP) or
"constant-pressure control" (CP).
In these control modes, the pump performance and consequently the
power consumption are adjusted according to the heat demand in the
system.
Proportional-pressure control
In this control mode, the differential pressure across the pump is
controlled according to the flow.
The proportional-pressure curves are indicated by PP1 and PP2 in the
Q/H diagrams. See 10. Pump settings and pump performance.
Constant-pressure control
In this control mode, a constant differential pressure across the pump is
maintained, irrespective of the flow.
The constant-pressure curves are indicated by CP1 and CP2 and are
the horizontal performance curves in the Q/H diagrams.
See 10. Pump settings and pump performance.