DAB KC, Instruction For Installation And Maintenance

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ENGLISH
18
6. ELECTRICAL INSTALLATION
ATTENTION!
ALWAYS RESPECT THE SAFETY
REGULATIONS!!
Electrical installation must be carried out by an
expert, authorised electrician, who takes on all
responsibility.
THE SYSTEM MUST BE
CORRECTLY AND SAFELY
EARTHED!!
Always switch off the mains power supply
before working on the electrical or mechanical
part of the system and make sure it cannot be
switched on again accidentally.
–
Ensure that the mains voltage and frequency are
the same as the values indicated on the
electrical data plate.
–
In the electrical connection to the power supply
line, fit a two-pole switch with contact opening
distance of at least 3 mm on all poles.
6.1 Motor protection
The motor must be connected to a manually
resettable motor protector. Set the motor protector
according to the rated current of the motor (I
1/1
).
See the identification plate.
6.2 Electrical connection
Make the electrical connections as indicated in the
wiring diagram inside the cover of the terminal
board.
Fig. 3
6.3 Operation with a frequency
converter
–
All three-phase motors can be connected to a
frequency converter. The recommended frequency
range with the standard pump motor is between 30
and 50 Hz, that is between 60 and 100% of the
rated speed.
–
The maximum length of the cable between the
motor and the frequency converter is 5 metres.
–
Depending on the type of frequency converter,
there may be an increase in motor noise. The motor
may also be subject to dangerous voltage peaks.
–
Problems such as voltage peaks or increased noise
may be eliminated by fitting a suitable LC filter
between converter and motor.
7. START-UP
DO NOT START THE PUMP WITHOUT
HAVING COMPLETELY FILLED IT
WITH LIQUID.
7.1 Filling with liquid
ATTENTION!
The system might be under pressure
and the liquid coming out might have
a very high temperature. Take the
necessary precautions to ensure that
the liquid does not cause personal
injuries or damage to other
components.
1 Close the interception valve on the delivery side of
the pump.
2 Completely open the interception valve on the
suction side before starting the pump.
3 Remove the filling cap. Fig. 4.
4 Completely fill the pump body and the suction pipe
with liquid until a constant flow of liquid comes out
of the filling hole.
5 Fit the filling cap and tighten it.
6 Slowly open the interception valve on the delivery
side while the pump is running to ensure the venting
and build-up of pressure during starting.
The discharge valve must be opened
as soon as the pump is started to
avoid the excessive increase in
temperature of the pumped liquid and
consequent damage of the materials.