TLT-Turbo GmbH
Installation, operating and maintenance instructions.
For axial flow fans
Page 9
Series fan division
Bad Hersfeld
Type AXO ... / ...
of 12
MBW-AXO.DOC
Issue: 03.2004
The impellers of our fans were balanced according to ISO 1940 quality G 6.3.
Since after installation of the fan the system may cause vibrations, during startup
appropriate measures have to be taken to reduce vibrations to a minimum
according to VDI 2056 machine group T.
This especially applies to fans with several speeds or variable speed, where
vibrations have to be measured over the complete speed range.
The fan should not be operated in a stall (bad air inlet or resistance of the machine
higher than expected). It has to run at the operating point it was designed for
(measure air quantity and pressure increase and compare the values with the
nameplate.)
12. Breakdowns
If after some time the fan starts vibrating, the cause may be the following:
a) Particles sticking on the impeller blades.
Troubleshooting:
clean the impeller, retighten the screws, check the weld
seams of the housing.
b) Impeller corroded.
Troubleshooting:
Clean and rebalance the impeller, unless heavily corroded.
Retighten the screws. Check the weld seams of the housing.
Other possible deficiencies
a) Fan does not start.
Troubleshooting:
check power supply, check motor
b) Impeller rubbing.
Troubleshooting:
Check if there are any particles on the impeller
, check
fastening of the motor.
c) Protective motor switch triggers when starting the fan.
Troubleshooting:
Check if the motor turns hard (bearing and winding
damaged), check power supply, check blade adjustment angle.
d) The fan does not reach its rated output.
Troubleshooting:
Clean the impeller, clean the duct system (all flaps open?),
was the duct system changed?
