DAB CP, Instruction For Installation And Maintenance

Page: 19 / 80

ENGLISH
13
8. INSTALLATION
− To protect the pump against deposits, it is advisable
to install it in the lowest point of the system. Fit the
pump in the plant only after having completed the
welding works and checked that the plant is quite
clean.
− The electropump must be fitted in a well ventilated
place, protected from unfavourable weather
conditions and with an environment temperature not
exceeding 40°C.
(Fig.B)
. Electropumps with degree
of protection IP55 may be installed in dusty and
damp environments. If installed in the open,
generally it is not necessary to take any particular
steps to protect them against unfavourable weather
conditions.
− The pump may be fitted either on the delivery or on
the return pipe, with the motor axis in horizontal or
vertical position, as long as the terminal board box is
never facing downwards
(Fig.C)
so as to avoid
dangerous water infiltrations in the case of leaks.
− To facilitate checking and replacement operations,
install the pump in a position with easy access.
− The arrows on the pump body indicate the direction
of flow. It is recommended to use interception gate
valves on the intake and delivery pipes, to prevent
drainage of the system when it is to be repaired. Fit
also a by-pass circuit between delivery and intake to
guarantee minimum recycling if electrovalves are
used in the pipes, so as to avoid the creation of
dangerous temperature rises.
− Ensure that the plant is provided with an air bleeding
system and that the expansion chamber (if provided)
is installed before the intake aperture. If the pump is
installed on the delivery of an open vessel circuit,
ensure that the safety pipe is connected before the
pump.
− When fitting the pump on the system, ensure that
the metal pipes do not weigh down on the pump
body, transmitting excess forces or stress that could
cause cracks or breakages.
− To avoid transmitting noise and vibrations, fit
vibration-damping couplings
on the intake and
delivery apertures.
9. ELECTRICAL CONNECTION
Caution! Always follow the safety regulations!
Scrupulously follow the wiring
diagrams inside the terminal
board box and those on page 67 of
this manual.
−
The electrical connections must be made
exclusively by skilled personnel as required by the
safety regulations in force.
The requirements of the electric energy supply
company must be scrupulously complied with.
In
the case of three-phase motors with star-delta start,
ensure that the switch-over time from star to delta is as
short as possible and that it falls within
table B on page 66.
− Before opening the terminal board and working on the
pump, ensure that the
power has been switched off.
− Check the mains voltage before making any
connection. If it is the same as the voltage on the data
plate, proceed to connect the wires to the terminal
board,
giving priority to the earth lead. (Fig. D).
−
ENSURE THAT THE EARTH SYSTEM IS EFFICIENT
AND THAT THERE IS THE POSSIBILITY OF
MAKING A GOOD CONNECTION!
− The pumps must always be connected to an external
switch.
− Single-phase motors are provided with thermal
overload protection and may be connected directly to
the mains.
− Three-phase motors must be protected with special
remote-control motor-protectors calibrated for the
current shown on the plate.
− In systems where twin pumps are fitted, provide
separate wiring and switches for each pump so as to
ensure continuous service.
10. STARTING UP
As well as being at high temperature
and high pressure, the fluid in the
system may also be in the form of
steam!
DANGER OF BURNING!
It may be dangerous even to touch
the pump or parts of the system.
Before starting up you must fill the system with water and
bleed the air. Bleed the residual air from the pump body
through the bleeding cock provided until only water comes
out
(Fig. E)
. This ensures that the mechanical seal is well
lubricated and that the pump immediately starts to work
regularly.
Dry operation, even for brief periods, causes
irreparable damage to the mechanical seal.
− Switch on the power and, on three-phase versions,
check that the motor is turning in the right direction, that
is clockwise when viewed from the fan side,
(Fig. F)
.
Otherwise invert any two phase leads, after having
disconnected the pump from the mains.
− With the pump running, check the supply voltage at the
motor terminals, which must not differ from the rated
value by +/- 5%
(Fig. G)
.
− With the unit at regular running speed, check that the
current absorbed by the motor does not exceed the
value on the data plate.