6
LEROY-SOMER
InstallatIon and maIntenance
LSA 40 - 4 POLE
ALTERNATORS
4455 en - 10.2009 / a
INSTALLATION
3 -
Personnel undertaking the various operations
discussed in this section must wear the appropriate
personal protective equipment for mechanical and
electrical hazards.
Assembly
3.1 -
All mechanical handling operations must be
undertaken using approved equipment and the
alternator must be horizontal. Check how much the
alternator weighs (see 4.7) before choosing the
lifting tool. During this operation, do not allow
anyone to stand under the load.
Handling
3.1.1 -
the generously-sized lifting rings are for handling the alternator
alone. They must not be used to lift the genset. The choice of
lifting hooks or handles should be determined by the shape of
these rings. Choose a lifting system which respects the integrity
and the environment of the alternator.
Coupling
3.1.2 -
Single bearing alternator
3.1.2.1 -
Before coupling the two alternators, check that both are
compatible by:
- Undertaking a torsional analysis of the transmission.
-Checking the dimensions of the flywheel and its housing, the
flange, coupling discs and offset.
When coupling the alternator to the prime mover,
the holes of the coupling discs should be aligned
with the flywheel holes by rotating the engine
flywheel. Do not use the fan to turn the alternator
rotor. Make sure the alternator is securely bedded in
position during coupling.
Tighten the coupling discs screws to the recommended torque
and check that there is lateral play on the crankshaft.
Two-bearing alternator
3.1.2.2 -
- Semi-flexible coupling
Careful alignement of the machines by measuring the
concentricity and parallelism of the two parts of the coupling is
recommended, the difference between the teadings should
not exceed the specified values (say 0,1 mm).
WARNING
This alternator has been balanced with a 1/2 key.
Location
3.1.3 -
Ensure that the ambient temperature in the room where the
alternator is placed cannot exceed 40°C for standard power
ratings (for temperatures above 40°C, apply a derating
coefficient). Fresh air, free from damp and dust, must be able
to circulate freely around the air input louvres on the opposite
side from the coupling. It is essential to prevent not only the
recycling of hot air from the machine or engine, but also exhaust
fumes.
Inspection prior to first use
3.2 -
Electrical checks
3.2.3.1 -
Under no circumstances should an alternator, new
or otherwise, be operated if the isolation is less than
1 megohm for the stator and 100,000 ohms for the
other windings.
There are two possible methods for restoring the above
minimum values.
a) Dry out the alternator for 24 hours in a drying oven at a
temperature of approximately 110 °C.
b) Blow hot air into the air input, having made sure that the
alternator is rotating with the exciter field disconnected.
c) Run in short-circuit mode (disconnect the AVR)
- Short-circuit the output phases using connections capable of
supporting the rated current (try not to exceed 6 A/mm2).
- Insert a clamp ammeter to monitor the current passing through
the short-circuit connections.
- Connect a 48 Volt battery in series with a rheostat of
approximately 10 ohms (50 Watts), to the exciter field terminals,
respecting the polarity.
- Open fully all the alternator orifices.
- Run the alternator at rated speed . Adjust the exciter field
current using the rheostat to obtain the rated output current in
the short-circuit connections.
Note: Prolonged standstill: In order to avoid these problems,
we recommend the use of space heaters, as well as turning
over the alternator from time to time. Space heaters are only
really effective if they are working continuously while the
alternator is stopped.
WARNING
Ensure that the alternator has the degree of
protection matching the defined environmental
conditions.
WARNING
Summary of Contents for LSA 40-4 POLE
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