Balancing; Installation Conditions; Alignment; Electrical Connection - MarelliMotori M8B 315 Instructions And Safety Information

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.

3.3. Balancing

Unless otherwise indicated the rotor is balanced dynamically with a half-key fitted on the shaft extension, in compliance with IEC 34-14.

3.4. Installation conditions

Install the generator in a ventilated room. If installed in closed areas the alternators should have a possibility to exchange the cooling air
directly with atmosphere. Air outlet and inlet openings should not be obstructed: provisions should be taken to prevent obstacles from
obstructing ventilation openings. The inlet of warm air should be avoided.
Provision should be taken to make inspection and maintenance easy when the generator is installed or during operation.

3.5. Alignment

Carefully align the generator and the driving machine.
Inaccurate alignment may lead to vibrations and damage of the bearings.
It is also necessary to verify that the torsional characteristics of generator and driving machine are compatible. In order to allow
torsional analysis calculation (at customer's charge); MarelliMotori can provide rotor drawings for torsional analysis purposes.
For single bearing generators it is further necessary to verify all dimensions of the flywheel and flywheel housing. Furthermore it is
necessary to check the dimensions of the coupling and of the flange on the generator.

3.6. Electrical connection

Standard generators are supplied with 6 leads.
Terminal arrangement permits star and delta connection, according to following diagrams.
If delta connection is strictly required (for 400 and 500 framesizes), it is necessary to specify it in the order (in such case the connection
bridges to perform the connection will be supplied).
It is anyway necessary, when changing the connection from star to delta, to check and modify the connection to the voltage regulator,
according applicable diagrams.
M8B 315
W2 U2 V2
U1 V1 W1
L1 L2 L3
M8B 400 - M8B 500
W2 U2 V2
U1
L1
V1
L2
W1
L3
Internal connection diagrams are shown at the end of manual for standard generators with 6 terminals and for those with 12 leads (9 or
12 terminals)
Direction of rotation
Generators are normally supplied to operate correctly when rotating clockwise (looking from shaft end side).
Grounding
Inside the terminal box there is a terminal for grounding, and a second terminal is on a foot of the generator. Grounding has
to be carried out using a copper wire of suitable size, in compliance with applicable standards.

3.7. Commissioning

Before starting up check insulation resistance:
THE GENERATOR MUST NOT BE OPERATED IF INSULATION RESISTANCE IS BELOW 5 MEGAOHM
Wiring diagrams for standard generators
STAR CONNECTION
L1
U1
U2
W2
V2
V1
W1
L3 L2
13
M8B 315
W2 U2 V2
U1 V1 W1
L1 L2 L3
M8B 400 - M8B 500
W2 U2 V2
U1
L1
V1
L2
W1
L3
ENGLISH
DELTA CONNECTION
L1
W2
U1
W1
U2
V1
V2