Lowara NSC2 Manual De Instalación, Funcionamiento Y Mantenimiento página 20

en - Original instructions
Tighten the cable glands carefully to ensure pro-
tection against cable slipping and humidity en-
tering the terminal box.
4. If the motor is not equipped with automatic reset
thermal protection, then adjust the overload pro-
tection according to the list below.
– If the motor is used with full load, then set
the value to the nominal current value of
electric pump (data plate)
– If the motor is used with partial load, then set
the value to the operating current (for exam-
ple measured with a current pincer).
– If the pump has a star-delta starting system,
then adjust the thermal relay to 58% of the
nominal current or operating current (only for
three-phase motors).
5 Commissioning, Startup,
Operation, and Shutdown
Precautions
WARNING:
• Make sure that the drained liquid
does not cause damage or injuries.
• The motor protectors can cause the
motor to restart unexpectedly. This
could result in serious injury.
• Never operate the pump without the
coupling guard correctly installed.
CAUTION:
• The outer surfaces of the pump and
motor can exceed 40ºC (104ºF) dur-
ing operation. Do not touch with any
part of the body without protective
gear.
• Do not put any combustible material
near the pump.
NOTICE:
• Never operate the pump below the minimum rat-
ed flow, when dry, or without prime.
• Never operate the pump with the delivery ON-
OFF valve closed for longer than a few seconds.
• Never operate the pump with the suction ON-
OFF valve closed.
• Do not expose an idle pump to freezing condi-
tions. Drain all liquid that is inside the pump. Fail-
ure to do so can cause liquid to freeze and dam-
age the pump.
• The sum of the pressure on the suction side
(mains, gravity tank) and the maximum pressure
that is delivered by the pump must not exceed
the maximum working pressure that is allowed
(nominal pressure PN) for the pump.
• Do not use the pump if cavitation occurs. Cavita-
tion can damage the internal components.
5.1 Fill the pump
For information about additional pump connections,
see Figure 14 (page 341).
Installations with liquid level above the pump
(suction head)
20
For an illustration that shows where pump plugs are,
see Figure 15 (page 343).
1. Close the on-off valve located downstream from
the pump.
2. Remove the fill (3) or gauge plug (1) and open
the on/off valve upstream until the water flows
out of the hole.
a) Close the fill (3) or gauge plug (1).
Installations with liquid level below the pump
(suction lift)
For an illustration that shows where pump plugs are,
see Figure 16 (page 345).
1. All pipe system empty:
a) Open the on-off valve located upstream from
the pump.
b) Remove the fill plug (3) and the gauge plug (1).
Use a funnel to fill the pump through the fill hole
until the water flows out of this hole.
c) Tighten the fill plug (3) and the gauge plug (1).
2. Filled discharge pipe system:
a) Open the on-off valve located upstream from
the pump and open the on-off valve down-
stream.
b) Remove the gauge plug (1) until water flows out
of this hole.
c) Tighten the gauge plug (1).
5.2 Check the rotation direction (three-
phase motor)
Follow this procedure before start-up.
1. Locate the arrows on the adaptor or the motor
fan cover to determine the correct rotation direc-
tion.
2. Start the motor.
3. Quickly check the direction of rotation through
the coupling guard or through the motor fan
cover.
4. Stop the motor.
5. If the rotation direction is incorrect, then do as
follows:
a) Disconnect the power supply.
b) In the terminal board of the motor or in the elec-
tric control panel, exchange the position of two
of the three wires of the supply cable.
For the wiring diagrams, see
341).
c) Check the direction of rotation again.
5.3 Start the pump
The responsibility for checking the correct flow and
the temperature of the pumped liquid rests with the
installer or owner.
Before starting the pump, make sure that:
• The pump is correctly connected to the power
supply.
• The pump is correctly filled according to instruc-
tions in Fill the pump (chapter 5).
• The on-off valve located downstream from the
pump is closed.
Figure 13 (page