4. START-UP
4.1 ELECTRICAL START-UP INSPECTION
4.1.0 General points
Electrical connections (auxiliaries, safeties and power
connections) must comply with the schematics provided.
Refer to Section 5 to get the concerned schematics
DANGER:
Check that all safety equipment operates correctly.
4.1.1 Winding Insulation
The insulation and the polarization index must be
measured on start up and then as per chapter 5.1.0
recommendation.
To measure the insulation (refer to chapter 5.10)
4.1.2 Electrical connections
The phases must be connected directly to the machine
links (with no spacers or washers, etc).
Make sure that the lugs are sufficiently tightened.
CAUTION:
ALL CURRENT TRANSFORMERS MUST BE
CONNECTED BEFORE START UP. IF CURRENT
TRANSFORMER NOT USED ITS OUTPUT MUST BE
SHORTED
4.1.3 Parallel operation
4.1.3.1 Definition of parallel operation
• Between machines
Operation mode named by Leroy Somer "1F"
At least two alternators are connected in parallel to supply
a load
The Automatic Voltage Regulator is in voltage regulation
mode
A droop Current Transformer is necessary to share the
reactive load
• With the mains
Operation mode named by Leroy Somer "3F"
At least one alternator is connected in parallel with the
mains (Public electricity network)
The Automatic Voltage Regulator is in Power Factor
regulation mode
4.1.3.2 Possibility of parallel operation
CAUTION:
PARALLEL OPERATION CAN ONLY BE USED FOR
ALTERNATOR ENGINEERED FOR SUCH OPERATION
4.1.3.3 Parallel coupling
CAUTION:
A WRONG SYNCHRONIZATION CAN LEAD TO MAIN
DAMAGES (HIGH MECHANICAL OVERTORQUE AND
OVER CURRENT)
During synchronization the following values must not be
overpass:
Max frequency shift :
0,1 Hz
Max phase offset :
10° (electrical angle)
Max voltage (phase - neutral) between machines :
(at phase offset =0)
5 % of the nominal voltage
In case of wrong synchronization, or mains micro
interruption inducing a fault over the indicated limits Leroy
Somer will not be considered as responsible of the
damages.
4.2 MECHANICAL START-UP INSPECTION
4.2.0 General points
4.2.0.1 Alignment ; fixing ; prime mover
The installation must comply with the manufacturer’s
installation rules for drive machine (alignment, mounting).
An arrow on the stator, indicates the direction of rotation.
4.2.0.2 Cooling
The air inlet and exhaust must be unobstructed.
The cooling auxiliaries (water circulation in the cooler, etc)
must be operating.
4.2.0.3 Lubrication
Lubrication must be carried out as per chapter 5. Lubricant
quantity and periodicity as per Section 1
4.2.1 Anti friction bearing machines start up
The bearings are pre-lubricated in the factory, but before
they are put into service, it is necessary to re grease in
order to fill the free spaces in the greasing circuit and to
evacuate the storage grease.
CAUTION
UPON START-UP, GREASE THE MACHINE WHILE IT IS
RUNNING.
Record the temperature of the bearings during the initial
operating hours. Poor lubrication can cause abnormal
heating.
If the bearing hisses, lubricate it immediately. Some
bearings may make a clattering noise if they do not operate
at normal temperature. This may occur if the weather is
very cold or when the machine is operating under abnormal
temperature conditions (start-up phase, for example). The
bearings will become quieter after having reached their
normal operating temperature.
Electric Power Generation
Installation and maintenance
5654
en - 2017.
10
/
a
LSA 5
2
.2
MHV
Industrial Range Alternators
- 4 pole
16
