Installing The Pump; Pump Control - Grundfos PS.G Serie Montage- Und Betriebsanleitung

6. Sizing
The pit volume depends on the wastewater flow rate and the
pump performance.
If the liquid in the pit is static during long periods, sediments may
build up in the pit sump. The pump should therefore be started at
least twice every 24 hours.

6.1 Installing the pump

For installation and startup of the pump, see the installation and
operating instructions for the pump.
Lower the pump carefully into the pit in order to
Caution
avoid damage to pump and pit.
Warning
The lifting equipment used for lifting the pump
must be rated for the weight of the pump,
approved and maintained according to local
regulations.
Warning
Chains supplied by Grundfos are marked with
maximum load and production date. The
maximum load must not be exceeded.
Maintenance must be carried out according to
local regulations.
We recommend that you check chains and
shackles supplied by Grundfos at least once per
year for cracks, corrosion or other irregularities.
If any defects are found, replace the chain or
shackles.

7. Pump control

If the pit is equipped with an AUTO
Note controlled pump, an external level controller is
not needed.
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 1-pump operation, the start level switch must 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 multipump operation, the start level switches
must be installed in such a way that pump is started before the
liquid level reaches the lower edge of the bottom inlet pipe.
• 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 pump controller selected.
7.1 Start and stop levels
The effective volume of the pump 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.
7.2 Installing the control system
See the installation and operating instructions for the control
system.
7.3 Installing the level control system
7.3.1 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
float switches.
Note
Fig. 22 Adjusting the float switches
A
B
C
ADAPT
Caution
7.3.2 Pressure transducer
If a pressure transducer is used, install in a protective pipe in
order to prevent contamination and deposits.
7.3.3 Other types of level control equipment
See the installation and operating instructions for the equipment.
8. Electrical connection and starting up the
product
See the installation and operating instructions for the pump and
the control system.
Note
Note that the bottom float switch (stop) must stop
the pump before the level in the pit falls below
the minimum level of the pump. See the
installation and operating instructions for the
pump.
A
B
Min. 300 mm
50 to 100 mm
Deactivation range 110 mm
Distance B must not be too big as otherwise the
float switch may get stuck in other parts of the
installation.
Warning
The electrical connection must be carried out by
an authorised person in accordance with local
regulations.
Warning
The pump or pump controller must be connected
to an external emergency stop.
If a power supply circuit breaker is used as
emergency stop, it must fulfil EN 60204-1, 10.8.4.
Warning
Before starting work on the pump or valves,
make sure that the fuses have been removed or
the main switch has been switched off.
Make sure that the power supply cannot be
accidentally switched on.
Do not install Grundfos control boxes and the
free end of the supply cable inside the pumping
station.
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