Electric Power Generation
1
Installation and maintenance
1
5
8
76 en - 2020.01 /
a
TALA44
Low Voltage Alternators - 4 pole
4.3 - Bearings
The bearings are permanently greased
Approximate life of the grease (depending on use)= 20,000
hours or 3 years.
4.4 - Mechanical defects
Fault
Action
Excessive overheating of one or - If the bearing has turned blue or if the grease has turned
Bearing
bath bearings
(bearing temperature 80
°
C above
black, chan�e the bearing.
- Bearing not ully locked (abnormal play in the bearing cage)
the ambient temperature)
- End shields incorrectly aligned
Excessive overheating of
-Air flow (inlet-outlet) partially clogged or hot air is being
recycled from the alternator or engine
Abnormal alternator frame (more than
-Alternator operating at too high a voltage (>105% of Un on
temperature 40
°
C above the ambient
load)
temperature)
-Alternator overloaded
- Misalignment (coupling)
Too much vibration
- Defective mounting or play in coupling
Vibrations
- Rotor balancing fault (Engine -Alternator)
Excessive vibration and humming - Phase imbalance
noise coming from the machine - Stator short-circuit
- System short-circuit
- Misparalleling
Abnormal Alternator damaged by a
Possible consequences
noise
significant impact, followed by
- Broken or damaged coupling
humming and vibration
- Broken or bent shaft end
- Shifting and short-circuit of main field
- Fan fractured or coming loose on shaft
- lrreparable damage to rotating diodes/AVR, surge suppressor
16
LEROY-SOMER '"
