Brochure

5.2.3 Control modes, ALPHA2 26-99
Internally controlled
ALPHA2 26-99 circulator pumps are designed for systems
with variable flow rates, where the pump is internally
controlled via a user interface.
ALPHA2 26-99 circulator pumps automatically control the
differential pressure by adjusting the pump performance to
the actual heat demand without the use of external
components. Two different control modes are available:
Proportional pressure
• Proportional pressure with the differential pressure
increasing at increased flow.
TM073148
Proportional pressure
Constant pressure
• Constant pressure with the differential pressure kept
constant.
TM073147
Constant pressure
Grundfos AUTOAdapt
The Grundfos AUTOAdapt function enables the circulator to
control the pump performance automatically within a defined
performance range:
• Adjusting the pump performance to the size of the
system.
• Adjusting the pump performance to the variations in load
over time.
Two different control modes are available for Grundfos
AUTOAdapt:
• Proportional Pressure AUTOAdapt. In proportional
pressure AUTOAdapt, the circulator is set to proportional-
pressure control.
TM073146
Proportional Pressure AUTOAdapt
•
Constant Pressure AUTOAdapt. In constant pressure
AUTOAdapt, the circulator is set to constant pressure
control.
TM073145
Constant Pressure AUTOAdapt
ALPHA
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Operation