Installing The Level Switches; Start And Stop Levels; Installing The Pump Controller; Float Switches - Grundfos PS.R.05 Montage- Und Betriebsanleitung

6. Installing the level switches

If the pit is equipped with an Auto
pump, an external level controller is not needed.
See the installation and operating instructions for the level control
system.
When installing the level switches, observe the following points:
• To prevent air intake and vibrations in the pump, the stop level
switch must be fitted in such a way that the pump is stopped
before air is sucked into the pump.
• In the case of one-pump operation, the start level switch
should be installed in such a way that the pump is started at
the required level; however, the pump must always be started
before the liquid level reaches the lower edge of the bottom
inlet pipe.
• In the case of two-pump operation, the start level switches
should be installed in such a way that pump two is started
before the liquid level reaches the lower edge of the bottom
inlet pipe, and so that pump one is started correspondingly
earlier.
• The high-level alarm switch must always be installed about
100 mm above the start level switch; however, the alarm must
always be given before the liquid level reaches the inlet pipe.
For further settings, see the installation and operating instructions
for the level switch selected.

6.1 Start and stop levels

The effective volume of the pit must be so large that the number
of starts does not exceed the maximum permissible number. See
the installation and operating instructions for the pump.

6.2 Installing the pump controller

See the installation and operating instructions for the pump
controller.
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6.3 Float switches

If float switches have been selected, they can be fitted on a tube
which can be lifted out of the pit. This ensures easy adjustment of
-controlled
ADAPT the float switches.
Fig. 16 Adjustment of float switches
A
B
C
The pit inlet must not be located within the area shown in fig. 17,
as it will disturb the function of float switches.
Fig. 17 Location of inlet
Note that the bottom float switch (the stop switch)
must stop the pump before the liquid level in the pit
falls below the minimum level of the pump. See the
installation and operating instructions for the pump.
A
B
Minimum 300 mm
50 to 100 mm
Operating range 110 mm
Distance B must not be too big as otherwise the float
switch may get stuck in other parts of the installation.
200 200
C