Nidec LSA 52.3 - Terminal Box Start-Up; Vibrations; Start-Up Sequences; Machine Stopped Checks

Electric Power Generation
Installation and maintenance
5382 en - 2022.11 / h
LSA 52.3 / LSA 53.2 / LSA 54.2
Industrial Range Alternators
__________________________________________________________________________________________________
16
4.2.2 Terminal Box start-up
The terminal box is mounted on damper pads.
CAUTION:
BEFORE THE ALTERNATOR STARTS, ALL FOUR
BLOCKING SYSTEMS FOR TRANSPORT MUST BE
DISASSEMBLED.
CAUTION:
THE BLOCKING SYSTEMS FOR THE TRANSPORT OF
THE TERMINAL BOX MUST BE INSTALLED EACH
TIME THE ALTERNATOR IS TRANSPORTED (ALONE
OR WITH ITS MOTOR).
The four locking brackets (each fastened by 4 M10 screws;
red parts in the diagram above) must be removed and kept.
4.2.3 Vibrations
The vibration measurement must be taken on each bearing
in all three directions. The measured levels must be lower
than the specified values indicated in the chapter 2.1.3.4.
Adjust the sensor as per chapter 2.1.3.4.
4.3 START-UP SEQUENCES
Start-up (commissioning) of the generator must follow the
following sequences:
4.3.1 Machine stopped checks
Mounting of the machine as per chapter 4.2.
Alignment as per chapter 3.3.
Cooling as per Chapter 4.2.0.2 & 4.2.3.
Lubrication of bearings as per Chapter 4.2.2.
Electrical connections as per chapter 4.1.2.
Winding insulation as per chapter 5.10.
4.3.2. Machine running checks
4.3.2.0 Rotor speed ramp-up (Standard Machine)
There are no restrictions on the rate of rotor speed
increase between stop and rated speed.
There is no restriction regarding the rate of load
application.
4.3.2.1 Checks of machine running without excitation
Run the generator without excitation by steps to verify the
bearings temperature as per chapter 2.5.1 or 2.6.2.
At the nominal speed (not excited) measure the vibrations.
Check that the vibration level is in accordance with the use
of the generator (as per chapter 2.1.3.4).
4.3.2.2 Checks of excited machine running with no load
In manual AVR voltage regulation mode, check the
excitation current value (refer to Section 4 for more
information on manual AVR mode and to Section 2 for the
generator test report).
In AVR automatic mode; Voltage adjustments; Voltage
range; check the excitation current value (refer to Section 4
for the AVR manual and to Section 2 for the generator test
report).
At the nominal speed (excited) measure the vibrations.
Check that the vibration level is in accordance with the use
of the generator (as per chapter 2.1.3.4).
4.3.2.3 Generator and site safety parameter
Adjust the site safety systems (surge voltage relay, surge
current relay, residual current protection, negative
sequence relay, etc.) The setting points are not in the
Leroy-Somer scope of supply.
The settings must comply with the generator data sheet
(e.g. capacity curve; thermal damage curve, etc.).
Check the synchronizer setting as per chapter 4.1.3.3.
For any operation at a speed exceeding the nominal range
(generally the main frequency +3%) the generator
excitation must be shut off (refer to the electrical
schematics).
4.3.2.4 Checks of machine running under full load
checks
Grid-coupled operation.
Adjust the Power Factor.
Progressively apply load to the generator:
Check the excitation current at 25% of the rated load.
Check the excitation current at 100% of the rated load.
At the nominal speed (full load) measure the vibrations.
Check that the vibration level is in accordance with the use
of the generator (as per chapter 2.1.3.4).