4
6.4 Vibrations
The fan is factory-balanced to minimise
vibrations during operation. If
vibrations occur, it usually indicates
accumulation of dust and dirt on the
impeller system. If the problem remains
after ordinary cleaning, please contact
professional assistance. Continuous
operation with vibrations may damage
both motor bearings and impeller.
Check the vibration dampers in the
suspension brackets for ruptures and
replace the dampers at signs of ruptures.
6.5 Motor
The motor has closed bearings that
should be changed in accordance with
the motor supplier's recommendations.
6.6 Removal of motors
Before start, follow the procedure in
section
Novenco recommends the use of a lift
and that only the motor arrangement is
taken down, instead of the entire fan
unit.
Removal of motors
1 Loosen the external motor cable
connector.
2 Remove the terminal box cover plate
and take out the terminal box. Turn
and affix the cover with a single screw
to the fan casing to facilitate work on
the terminal box (fig. 6).
3 Disconnect the motor cable in the
terminal box and loosen the internal
cable connector (1, fig. 7) at the
separation from the pressure
chamber. Push the cable fully into the
pressure chamber.
4 Prepare support of the motor
arrangement, e.g., with a lift, in order
to lift it as short as possible and
preferably straight down.
5 Loosen the motor arrangement (eight
M8x16) (1, fig. 8) from the fan casing
and take it down.
The arrangement requires two people
to take down safely. Make sure to pull
the motor cable completely free of the
fan casing.
6 Leave the wire guard affixed to the
inlet nozzle (2, fig. 8).
7 Remove the impeller by removing the
motor shaft screw (3, fig. 8).
8 Disconnect the motor from the inlet
nozzle. It is attached with eight 12x20
screws (4, fig. 8).
9 Slide the steel tube off the motor cable.
The motor is now ready for service. Refer
to the motor supplier’s instructions for
service.
6.7 Mounting of motors
Lubricate bolts with grease, before
screwing them in during reassembly.
Mounting of motors
1 Slide the steel tube onto the cables for
the new motor.
2 Affix the motor to the inlet nozzle
with the eight 12x20 screws (4, fig. 8).
3 Install the impeller on the inlet nozzle
and attach it to the motor shaft.
4 If the wire guard has been removed,
then affix it to the inlet nozzle with
four blind rivets 3.2x10 of stainless
steel grade A2 (2, fig. 8).
5 Support and place the motor
arrangement in the fan casing. Make
sure to pull the motor cable along the
same route as from the factory.
The arrangement is attached with
eight M8x16 screws (1, fig. 8).
6 Roll the motor cable up into the
terminal box room, before tightening
the connector at the separation from
the pressure chamber.
7 Connect the motor cable in the
terminal box and install it and the
cover (fig. 6).
8 Tighten the external motor cable
connector.
9 Connect the power supply for the fan
and follow the procedure in section
.
Figure 7.
Loosen internal connector
1
Figure 8.
Removal of motor
2
1
4
3
