Datasheet

ENGLISH
become a worrying
issue when the level
is unacceptable. This
noisecanbeidentified
as a noise caused by
air, mechanical parts,
electrical buzzing noise
or a combination of
these factors. Whilst
the noise caused by air
can increase because
of obstructions near
the fan inlet or outlet,
an excessive noise is
more commonly caused
by the wrong choice or
installation of the fan.
The impeller scrapes on the enclosure.
Bearings worn.
Eccentricity between rotor and stator.
Winding vibrations
Positioning in a resonant area
peripheral speed.
Checkthefittingpositionoftheimpellerand
the pipes; if needs be, correctly restore their
position.
Check the condition of the bearings; if needs
be, lubricate them or replace them with an
identical bearing.
Check that the axis is identical; if needs be,
restore or replace the electrical motor with a
suitable type.
Can be reduced with higher quality motors
Move the fan or use soundproofed casings
9.9 Too many vibrations Unbalanced rotating parts.
Unsuitable mounting structure: with a natu-
ral frequency close to the fan rotation speed
natural frequency.
Slackened screw connections
Defective bearings
Check impeller balance; if necessary, reset it to
the values shown in diagram 1. Check the drive
alignment or the pulley balance. Check that the
shafts are straight.
Strengthen and/or change the natural frequen-
cy of the mounting structure by using weights.
Tighten the nuts and bolts
Check the wear of the bearings (specially the
watertight bearings) and their lubrication.
Pag. 22