MarelliMotori MJB 250, Operation And Maintenance Manual

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ENGLISH
963857101_G
27
27
8.2 Mechanical anomaly
TROUBLE POSSIBLE CAUSE
REMEDY
(always to be done with the machine switched off)
Winding temperature
raised.
Air cooling temperature
raised.
a) High ambient temperature
b) Hot air reflow
c) Source of heat in the proximity
d) Plant of defective cooling
e) Loopholes of the air obstructed
f) Air filter very dirty
g) Reduced air flow
h) Defective of measurement System
i) Overload
j) Load with cosfì below to 0,8
k) Speed less than rated.
a) Ventilate in order to reduce the ambient temperature
b) Create sufficient free space around to the machine
c) Remove the heat sources
d) Inspect conditions system and correct assembly
e) Clean up the loopholes from eventual detritus
f) Clear or substitute the filter
g) Remove the obstacles, assure that the air flow is
enough
h) Check the thermodetectors
i) Eliminate the overload. To cool the genset before
restarting it
j) Verify the values of the load, cosfì must be 0,8 or to
reduce the load
k) Check rpm (frequency).
Noise, high vibrations.
a) Insufficient base structure or not
suitable antivibration, incorrect fixing to
the basement
b) Defective coupling
c) Defective cooling Fan, unbalanced rotor
d) Excess of unbalanced load, Single
phase loads
e) Malfunctioning bearing
a) Strengthen the basement, replace the antivibration,
cross again the screw on the base
b) Review the alignment, the fixing of the disc on they fly
motor and of the D-end shield on the first motor
c) Check and to repair the cooling fan, clean the rotor and
rebalancing
d) Check that the load is conforming to the requisite
e) Replace bearing
Bearings temperature
raised.
a) Malfunctioning bearing
b) Axial or radial load too high
a) Replace bearing
b) Check the alignment and check the coupling of the
genset
9. SPARE PARTS - NOMENCLATURE
Pos.
Part name
Type / Code
MJB 250 MJB 315 MJB 355
201 D side (D:E) bearing 6218 C3 / 346110114 6319 C3 / 346151095 6322 C3 / 346151110
202 N side (N.D.E.) bearing 6313 2Z C3 / 346114065 6315 2Z C3 / 346114075 6317 2Z C3 / 346114085
309 N° 3 rotating diodes (inverse) 41 HFR 80 / 963821112 71 HFR 120 / 963821170
310 N° 3 rotating diodes (direct) 41 HF 80 / 963821113 71 HF 120 / 963821171
311 Surge suppressor M16FA864A M40FA990A
119 Complete rotating rectifier M25FA648B M40FA500A