Inlet Pressure Protection - Grundfos CMBE Montage- Und Betriebsanleitung

7.3 Inlet pressure protection

Some models of the pump are fitted with an
adjustable pressure switch as inlet pressure
protection. The pressure switch is fitted to the inlet
manifold.
The inlet pressure setting may have to be adjusted
according to local regulations.
Pos. Description
1 Pressure switch valve
Before starting up the system, make sure
that the pressure switch valve is open.
If the inlet pressure is below the lower
switching point, the system cannot start.
If the pressure switch has stopped the
system during operation due to the inlet
pressure being too low, the inlet pressure
must increase to a pressure that is higher
than the setting of the upper switching
point before the system can restart.
If necessary, adjust the lower switching point by
turning screw A and adjust the upper switching point
to a value higher than the lower switching point by
turning screw B.See the figure below.
Do not set the lower switching point to a
value below the minimum inlet pressure.
A
1
Adjustment of switching points
Pos. Description
A Low-pressure switching point
B High-pressure switching point
B
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