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3.4.3 Electric Wiring
All the
CEHV
series cooling towers are equipped with electric motors usually ready for connection to a 3-phase
electrical supply [Fig. 09].
IMPORTANT !
All electric wiring must be performed by specialist personnel, also allowing for
the earthing of the motor.
Provide for the installation of a circuit-breaker with key nearby the motor-fan
set.
The electric motor must be controlled and protected by a remote motor
protection device, that can also permit control of the fan motor by means of
an ON/OFF thermostat, in function of the cold (outlet) water temperature.
NOTA
: all fans are checked and tested at the factory, nonetheless before making electric power connection to
the motor it is advisable to check that the fan rotates freely inside its cowling, by turning it by hand for
several complete turns and ensuring that there is a sufficiently large gap between the extremity of
every single blade and the inside surface of the ring.
NOTA: However always check the type of connection to be
effected in accordance with the wiring scheme provided by
the motor manufacturer on the plate inside the terminal
box.
Close the junction box, taking great care to ensure that
the gasket placed between the lid and the box itself is
correctly positioned and that the cable entries are
completely tightened.
To assure a greater degree of tightness/closure of the
juncture box, one can further make a suitable seal both of
the box itself and of the cable entries with an appropriate
silicon-based sealant.
[Fig. 09]
Once the electrical wiring has been completed, give an
impulse of electric current to the motor and check that the
direction of rotation of the fan is such that air is indeed
drawn in from the lower part of the cooling tower and
expelled from the top (i.e. from the fan).
If this is not the case, invert the rotation direction by simply
swapping over the positions of two of the three phases of
the power supply line, having previously cut-off the
electrical supply up-line [Fig. 10].
[Fig. 10]
