Piusi EX 50 12V, Руководство пользователя

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M0217 EN 29
EN
M1 POSITIONING, CONFIGURATIONS AND ACCESSORIES
NOTE The pump must be secured in a stable manner.
ATTENTION
It is the installer's responsibility to provide the line acces-
sories necessary for the safe and proper functioning of the
pump. The accessories that are not suitable to be used with
the previously indicated material could damage the pump
and/or cause injury to persons, as well as causing pollution.
To maximise performance and prevent damage that could
affect pump operation, always demand original acces-
sories.
M2 NOTES ON SUCTION AND DELIVERY LINES
DELIVERY
The selection of the pump model must be made taking into account the characteristics of
the system.
The combination OF: the length of the pipe, the diameter of the pipe, as well as the accessories
installed, could create back pressure that are greater than the maximum predicted pressure,
thereby causing the pump's electronic controls to intervene and reducing the dispensed flow
considerably.
In these cases, to guarantee correct operation of the pump, it is necessary to reduce the re-
sistance of the system using pipes that are shorter or that have a greater diameter, as well as
line accessories with smaller resistances (e.g. an automatic dispensing nozzle with greater flow
rate capacity).
SUCTION
FOREWORD
Self-priming pumps are characterized by excellent suction capacity.
During the start-up phase, when the suction pipe is empty and the pump is wet with the fluid,
the electric pump unit is able to suck liquid from a maximum vertical distance of 2m.
It is important to note that it could take up to 1 minute for the pump to prime and that the
presence of an automatic dispensing nozzle on the delivery side will prevent the air trapped
during the installation from being released and, therefore, the correct priming of the pump.
For this reason, it is always advisable to prime the pump without an automatic delivery nozzle,
verifying the proper wetting of the pump.
Always install a foot valve to prevent the suction pipe from being emptied and to keep the
pump wet at all times. In this way, the pump will always start up immediately the next times it
is used. When the system is in operation, the pump can operate with back pressures of up to
0.5 bars on the suction inlet; beyond this point, the pump may begin to cavitate resulting in a
drop of the flow rate and an increase in the noise levels of the system.
In light of this, it is important to guarantee small back pressures on the suction side, by using
short pipes with diameters that are equal to or larger than those recommended, reducing ben-
ds to a minimum, and using filters with a large cross-section and foot valves with minimum
possible resistance on the suction side. It is very important to keep the suction filters clean
because, when they become clogged, they increase the resistance of the system.
The vertical distance between the pump and the fluid must be kept as short as possible, and
it must fall within the 2m maximum required for priming. If the distance is greater, a foot valve
must be installed to allow the suction pipes to fill up and the diameter pipes must be larger. It is
however recommended that pump not be installed if the vertical distance is greater than 3m.
ATTENTION If the suction tank is higher than the pump, an
anti-siphon valve should be installed to prevent ac-
cidental diesel fuel leaks. Dimension the installation
in order to control the back pressures due to water
hammering
It is a good system practice to install vacuum and
air pressure gauges right at the inlets and outlets of
the pump, which allow verification that operating
conditions are within anticipated limits. To prevent
the suction pipes from being emptied when the pump
stops, a foot valve should be installed.
THE INSTALLER IS RECOMMENDED TO INSTALL A
SUCTION FILTER.