Doosan G625XF, Руководство по эксплуатации и техническому обслуживанию

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50 Hz: G625 - G690 - G750XW/XF
OPERATION & MAINTENANCE MANUAL 74 60 Hz: G655 - G750 - G800 - G850XW/XF
MECHANICAL DEFECTS
ELECTRICAL FAULTS
It is imperative to lubricate the alternator during operation and on first use.
Before using another grease, check for compatibility with the original one.
Fault Action
Bearing
Excessive overheating of one or
both bearings (bearing temperature
80°C above the ambient
temperature)(With or without
abnormal bearing noise).
- If the bearing has turned blue or if the grease has turned black,
change the bearing.
- Bearing not fully locked (abnormal play in the bearing cage).
- End shields incorrectly aligned.
Abnormal
temperature
Excessive overheating of alternator
frame (more than 40°C above the
ambient temperature).
- Air flow (inlet-outlet) partially clogged or hot air is being recycled
from the alternator or engine.
- Alternator operating at too high a voltage (>105% of Un on load).
- Alternator overloaded.
Vibrations
Too much vibration.
- Misalignment (coupling).
- Defective mounting or play in coupling.
- Rotor balancing fault (Engine - Alternator).
Excessive vibration and humming
noise coming from the machine. - Phase imbalance.
- Stator short-circuit.
Abnormal
noise
Alternator damaged by a significant
impact, followed by humming and
vibration.
- System short-circuit.
- Misparalleling.
Possible consequences.
- Broken or damaged coupling.
- Broken or bent shaft end.
- Shifting and short-circuit of main field.
- Fan fractured or coming loose on shaft.
- Irreparable damage to rotating diodes/AVR, surge suppressor.
Fault Action Effect Check/Cause
No voltage at
no load on
start-up
Connect a new battery of
4 to 12 volts to terminals
E- and E+, respecting
the polarity, for 2 to 3
seconds.
The alternator builds up and its
voltage is still correct when the
battery is removed.
- Lack of residual magnetism.
The alternator builds up but its
voltage does not reach the rated
value when the battery is
removed. - Check the connection of the voltage
reference to the AVR.
- Faulty diodes.
- Armature short-circuit.
The alternator builds up but its
voltage disappears when the
battery is removed.
- Faulty AVR.
- Field windings open circuit (check
winding).
- Revolving field coil open circuit (check
the resistance).
Voltage too
low
Check the drive speed.
Correct speed.
Check the AVR connections (AVR may be
faulty).
- Field windings short-circuited.
- Rotating diodes burnt out.
- Main field winding short-circuited -
Check the resistance
Speed too low.
Increase the drive speed (do not touch
the AVR voltage pot. (P2) before running
at the correct speed).