SPERONI CS Serie Instrucciones De Uso página 10

INSTRUCTIONS FOR THE INSTALLATION AND USE OF ELECTROPUMPS
1. General
This manual is meant to provide the user with the
essential information required for installing, using and
servicing the pumps.
A fault-finding chart indicating possible cause and
remedy for every problem which might occur, is
included.
2. Technical characteristics and materials
The electric pumps are the centrifugal, radial, close-
coupled type, with single impeller.
• Cast iron pump-body and support, stainless steel
threaded counter flanges.
• Stainless steel motor shaft; bronze impeller for the
high head range; cast iron impeller for the low head
range.
• Mechanical seal housing standardized to DIN 24960.
The mechanical seal is lubricated by the pumped
liquid.
• All the electric pumps come fitted with threaded
counter-flanges.
• Amply dimensioned ball-bearings pre-packed with
special grease for life.
• 2 pole electric motors of enclosed type, IP 55, with
external ventilation; insulated according to Class F.
• Standard supply voltages:
50 Hz=230/400 V
up to 7,5 kW - 400/700 V
for higher power ratings.
60 Hz=230/400 V for all powers.
Standard voltage V 230 - 50 Hz.
On request, special voltages available.
• In the standard versions the electric pumps are
suitable for fluid temperatures up to 90°C.
• Maximum working pressure: 10 Bar.
3. Applications
The electric pumps are suitable for application in the
civil, agricultural and industrial fields, to pump chemi-
cally or mechanically non aggressive liquids. Any
suspended solid particles should not exceed 2% by
weight. The following are but a few typical applications:
water supply systems, irrigation schemes, pressure
tank feed, pressure boosting, air conditioning system,
heating systems.
4. Installation
The pumps may also be located outdoor, provided
they are suitable protected by a roofing; they can also
be installed inclined or vertically.
Warning:
For operation in hot damp environments, the pump
should not be installed orientated to different directions
than normal, to avoid condensation water building up
inside the motor.
Avoid vertical position with motor facing down ward
(see installation diagram - Fig. 5).
Being generously dimensioned, these pumps can be
supported by the pipework of the system to which
they are applied, even though it would be preferable
- where possible - to secure them firmly to a bedplated
by means of four holding-down bolts fitted through
the holes provided in the pump feet. Firm mounting
will aid to damp down vibrations, if any.
A satisfactory installation should conform to the
following indications:
The suction pipe, the inside diameter of which should
never be smaller than the pump inlet, should be
dimensioned consistently with the system and the
pumped liquid. Bear in mind that the maximum theo-
retical suction lift not only is reduced by the NPSHr
required by the pump, which is a peculier characteristic
of the pump itself, but is also reduced by the height
above sea level of the installation and the friction
losses occurring in the suction line.
Therefore, in order to avoid cavitation, which would
generate noise, performance drop and vibrations that
might exert undue mechanicals stress on the pump,
the following relation should always be observed:
hp + hz ≥ (NPSHr + 0.5) + hf + hpv
where:
h
p
is the absolute pressure acting on the free surface of
the liquid in the suction reservoir, expressed in meters
of liquid. hp is the quotient between the barometric
pressure and the specific weight of the liquid.
h
z
is the difference in level between the pump axis and
the free surface of the liquid in the suction reservoir
expressed in metres. hz is negative when the liquid
level is below the pump axis.
h
f
is the head loss occurring within the suction line and
the fittings fitted to it, such as connectors, foot valve,
sluice valves, bens, etc.
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