ENGLISH
10
If the machine shows deviations from the normal performance (excessive or too low voltage, increase in temperature, noise and
vibrations) promptly advise the personnel responsible for maintenance.
WARNING: Here enclosed with this “instructions manual” there are self adhesive leaflets which are reporting symbols
for security: the self adhesive leaflets are to be applied to the generator surface, at the customer’s charge, according the
instructions presented on the sheet of the self-adhesive.
1. DESCRIPTION
These instructions refer to three-phase synchronous generators series M8B. Technical data and constructive details are given in the
catalogue.
In order to obtain the proper working of the generator it is necessary to read carefully all included instructions.
The generators M8B are synchronous generators, brushless type, self excited and self regulated, manufactured according to the
standards indicated on the name plate (IEC 34-1).
Degree of protection - characteristics
The protection degree of the generators and the rated data are shown on the name plate.
Frequency
The generators are suitable for operation at 50 and 60 Hz, according to the data reported on the name-plate: for correct operation
for 50 or for 60 Hz, it is necessary to verify that the settings of the voltage regulator are proper for the required operation and that the
use of the generator is in accordance with the values on the name-plate.
Accessories
According to the customer’s order the generators can be equipped with accessories, such as anticondensation heaters, thermistors,
etc.
2. TRANSPORT AND STORAGE
The generator is shipped ready for installation. It should be carefully inspected on arrival in order to verify if damage has occurred
during transport; if any, they should be referred directly to the haulier and to MarelliMotori
For lifting and handling the purpose made eyebolts must be used.
The lifting eyes are designed to support only the weight of the generator and they are not to be used for lifting the complete
gen-set that incorporates the generator. Check that the lifting means available are suitable for the movement of all parts which
have to be handled. Check also that all the working conditions are suitable to operate without dangers for safety of personnel.
If the generator is not put into operation immediately, it should be stored in a covered area or in a clean, dry and vibration-free place. If
it is stored in a damp ambient, the windings should be dried before using it.
The rolling contact bearings do not require maintenance during storage; periodic rotation of the shaft will help to prevent contact
corrosion and hardening of the grease.
3. INSTALLATION AND COMMISSIONING
3.1 Check before installation
Before installing the generator
- make sure that name plate data corresponds to the power supply and operating conditions and that the installation
complies with the manufacturer’s recommendations
- clean any protecting varnish from all connecting surfaces (such as surface of couplings and flanges and shaft
extension for two-bearing generators).
All two bearing generators M8B 250 are manufactured with axially located rotor (D.E. bearing is axially fixed).
Single bearing generators are shipped with a rotor securing plate, fixing the coupling to the flange. Before installation, remove the
plate.
3.2. Insulation test
If the alternator has been kept in storage for a long period of time, it is a good practice to test the stator windings for ground insulation
before starting up.
Before doing this test, it is necessary to disconnect the voltage control system (AVR or similar devices).
If this test, performed using a ohmmeter or another similar instrument, shows that ground resistance is below 5 Mohm, it is necessary
to dry the generator and then the test should be repeated.
