Grundfos ST-55-520, Инструкция по установке и эксплуатации

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3
2
TM079307
Stop levels for auto-coupling installations
Pos. Description
1 Installation S (Ex pumps)
2 Installation S (standard pumps)
3 Installation type C (standard and Ex pumps)
Ex pumps without a cooling jacket must al-
ways be completely submerged.
In case of an Ex pump, install an additional
level sensor for the stop level.
Set the stop level so the flow velocity in the pit
increases towards the end of the working cycle. In
pits with several different stop levels, such as in
frequency-controlled installations, program the control
sequence to pump down to the lowest stop level at
least once a day to clean out the bottom of the pit.
The stop levels are determined by the motor
submergence required to ensure cooling, prevent
cavitation or avoid air being sucked into the pump
inlet. The lowest level cannot always be predicted but
must be confirmed through tests during startup.
6.2.2 Start and stop levels for dry installations
Stop levels
The stop level setting for dry-installed pumps
depends on the inlet pipe height, shape and flow
velocity. Set the stop level approximately one inlet
pipe diameter above the inlet pipe. The final stop
level must be confirmed through test runs during
startup.
Start levels
In pits with dry-installed pumps, set the starting level
above the pump housing to ensure that the cooling
jacket is filled up before the pump starts. For vertical
pumps, this height may be considerable and must be
set with a margin.
G
S
D
F
D
p
1
E
Y
45°
TM058187
Vertical, dry installation (D)
Horizontal pumps do not require special
considerations for the start level if the inlet pipe is
designed to prevent air pockets from forming.
S
F
Z
E
D1
45°
TM046901
Horizontal, dry installation (H)
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English (GB)