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3.3 Proper usage
W A R N I N G
!
Improper usage!
S
Death, serious bodily injury, damage to property.
Z
Operate the pump only in the electrical network
compatible with the motor.
3.3.1 Pumped liquids
Only pure or slightly contaminated liquids with a maximum
particle size up to 0.0157 inch may be pumped. These liquids
may not chemically or mechanically attack the pump
materials or lower their strength. If liquids with a viscosity
greater than that of water are to be pumped, make sure that
the motor will not be overloaded. The pump may not be
operated beyond the maximum allowable values. Even short
periods of pressure overload (e.g., as a result of a pressure
surge) should be avoided.
3.3.2 Minimum flow rate Q
min
Do not operate the pump below minimum flow rate of
Q
min
= 10 - 15 % Q
opt
.
3.3.3 Connections and pipelines
The nominal diameters of the system pipelines should be
equal to or greater than the nominal diameters of the pump,
i.e., DNS (suction side) and DND (discharge side), and the
connecting elements to the pump must conform exactly to the
design standard/specification of the mating connector piece
installed on the pump. The suction line must be absolutely
leak-tight and laid in such a way that no air pockets can form.
Avoid tight elbows and do not install valves immediately
upstream of the pump. The suction head of the system may
not be greater than the suction head guaranteed by the pump.
Operation of the pump with NPSH less than that required by
the pump will result in noisy operation and or damage to pump
components.
3.3.4 Motor activation
Do not start and stop the motor more than 15 times per hour.
3.3.5 Design
All information and descriptions in this Operating Manual
concerning the use and operation of the pumps are based
exclusively on the standard designs.
These rules do not apply to special designs, to customer
specific modifications, or to random external influences which
may occur during use and operation.
3.4 Technical data
W A R N I N G
!
Overloading the pump!
S
Death, serious bodily injury, damage to property.
Z
Use the pump only under the indicated operating
conditions. Also avoid short over pressure situation (e.g.
caused by pressure surge).
