Colasit CMVpro 125-400 ATEX, Operating Instructions Manual, Page: 68 / 88

12 | Repair
68 / 88 Operating instructions CMVpro 125-400 ATEX | Version 1-en
Fault Possible cause Fault discovery Remedy
FC parameter "max.
frequency" set improp-
erly (speed too high,
overheating of electric
motor). Check FC parameters
_ Chap. 8.3.2 [ } 50].
Adjust parameters ac-
cording to characteris-
tic map in technical
data sheet.
Grinding noise
coming from
the impeller. Casing too tight. Check distance and
alignment of ductwork
to fan connection. Adjust ductwork dis-
tance and connection
(sleeves) appropri-
ately.
Ductwork connected to
fan without sleeves. Connect ductwork to
fan with sleeves
_
Chap. 7.8 [
}
41].
Loose impeller. Impeller loosened on
motor shaft? Check and tighten hub
adapter
_
Chap. 12.5 [
}
70].
Deposits or foreign ob-
jects between impeller
and inlet cover. Determine grinding
point.
Check with feeler
gauge.
Remove deposits or
foreign objects
_
Chap. 11.3.3 [
}
62].
Impeller defect. Visual inspection. Replace impeller
_
Chap. 12.5 [
}
70].
Audible sound
from bearings. Bearing damage. Auditory inspection. Replace motor bear-
ings or exchange mo-
tor
_ Chap. 12.7 [ } 73].
End of service life
reached.
Bearing damage due
to electrical discharge
machining (bearing
currents). Measure voltage be-
tween the motor shaft
and casing of the elec-
tric motor. Interference suppres-
sion measures with FC
operation; see FC
manufacturer’s guid-
ance. Check EMC
guidelines.
Use current-insulated
roller bearings or ce-
ramic hybrid bearings.
Excessive
leakage at im-
peller hub. Overpressure opera-
tion of the fan (without
optional hub seal). Pressure measure-
ment. Operate fan at nega-
tive pressure.
Install optional hub
seal.
Hub seal worn or de-
fective. Visual inspection. Replace sealing
_
Chap. 12.9 [
}
76].