ITT Lowara e-SV Series, Инструкция по установке и эксплуатации

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WARNING
WARNING
WARNING
WARNING
WARNING
WARNING
WARNING
WARNING
Do not use this pump/electric pump unit to handle
flammable and/or explosive liquids..
Do not use this pump to handle liquids
containing
abrasive, solid or fibrous
substances.
For special requirements, please contact the Sales and Service
Department.
Depending on the pump model and on the temperature of the
pumped liquid, the maximum operating pressure is shown in the
following chart.
-40 -30 -20 -10 +10 0 +30 +20 +50 +40 +70 +60 +90 +80 +110 +100 +130 +120
0
5
10
15
20
25
30
35
40
45
50 [bar]
E
P
D
M
F
P
M
P
T
F
E
[°C]
PN40
PN25
PN16
SV1125_M 0008_A _sc
3.1.3 Suction
In theory, a pump could suck water from a source located 10.33
meters lower than the pump’s own installation level, but this
does not happen because the pump offers its own intrinsic flow
resistance, moreover the suction capacity is reduced as a result
of flow resistance in the piping, height difference, liquid
temperature and elevation above sea level.
A wrong choice in the altimetric placement of the pump could
lead to cavitation.
With reference to Fig. C and given Z as the maximum height at
which the pump can be installed, with reference to the level of
the liquid source the following can be stated:
Z=p
b
• 10,2 – NPSH – H
f
- H
v
-0,5 [m]
p
b
Barometric pressure in bar, in closed systems it
shows system pressure
NPSH Value in [m] of the pump intrinsic flow resistance
H
f
Total losses in [m] caused by passage of liquid
through parts on the inlet side of the pump
0.50 Recommended safety margin in [m]
H
v
Steam pressure in [m] through the liquid
Temperature T [°C] (for additional information
Fig.C)
With the meanings given in the above table it can be stated that:
If Z
≥
0 the pump can work with a maximum suction height equal to
Z.
If Z<0 the pump must be provided with an inlet pressure equal
to –Z.
For additional information on SV-series performances
Fig.D
Do not use the pump if cavitation occurs, as
its internal components could be damaged.
If hot water is pumped, guarantee an
appropriate condition on the suction side to
prevent cavitation.
Make sure that the sum of the pressure on
the suction side (water mains, gravity tank)
and the maximum pressure delivered by the pump does not
exceed the maximum working pressure allowed (nominal
pressure PN) for the pump (
Fig.E).
p
1max
≤
PN - p
max
With the following meaning of the symbols:
p
max
Maximum pressure delivered by the pump
p
1max
Maximum inlet pressure
PN Maximum operating pressure
If a motor with an axially locked shaft (Lowara standard) is
used, ensure that the above formula is fulfilled, if not please
contact the Sales and Service Department.
3.1.4 Minimum nominal flow rate
Do not run the pump with the on-off valve
shut on the delivery side for longer than a
few seconds.
To determine minimum nominal flow rate Fig.G
3.1.5 Number of starts per hour
For electric pump units coupled to motors supplied by Lowara,
the maximum number of work cycles (starts and stops) in one
hour is as follows:
kW 0.25 0.37 0.55 0.75 1.1 1.5 2.2 3
n 60
kW 4 5.5 7.5 11 15 18.5 22 30 37 45 55
n 40 30 24 16 8 4
If a different motor is used instead of the
standard one supplied by Lowara, check the
relevant instructions to find out the maximum number of work
cycles allowed.
3.1.6 Installation Site
Protect the pump/electric pump unit from the
weather
(rain, wind,…) and freezing
temperatures. Provide adequate ventilation for motor cooling
purposes.
Ambient tempe0°C to +40°C.
Relative ambient humidity must not exceed 50% at +40°C.
For temperatures above +40°C and for
installation sites located at elevations of over
1000 meters above sea level, the motor must be derated (the
power it delivers must be decreased) to guarantee its proper
cooling. The motor may have to be replaced with a more
powerful one. Please check Fig.H and, when in doubt, please
contact the Sales and Service Department.
If the relative air humidity conditions are high, please contact
the Sales and Service Department.
Do not use the pump/electric pump unit in environments
that may contain flammable/explosive or chemically
aggressive gases or powders.
Provide adequate lighting and clearance around the
pump/electric pump unit. Make sure it is easily accessible for
installation and maintenance operations. Make sure that any
fluid leaks or other events of this nature will not lead to flooding
of the installation area and consequent submersion of the
pump/electric pump unit.
Liquid Temperature Minimum Maximum
- for standard version (EPDM gaskets): - 30°C + 120 ° C
- for special version (FPM gaskets): - 10 °C + 120 ° C
- for special version (PTFE gaskets): 0 °C + 120 °C
- for household and similar purposes (EN
60335-2-41): + 90 °C
Stainless Steel Flanges Cast Iron Flanges