Lister Petter T Series, Руководство оператора

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14
tHe eCo28 alternator operators' Handbook
Measuring the insulating earth
resistance can assess the condition of
the windings. This measurement can
be carried out with a "Megger" device,
or similar, with a 500V direct-current
voltage.
The winding resistance values are
given in "06.8 Winding Resistance
Values".
It is very important to disconnect the
following components before checking
resistance:
1. The voltage regulator.
Figure 5.4.1 Voltage Regulator
2. The rotating diode bride.
Figure 5.4.2 Diode Bridge
3. Any other device connected to the
windings to be checked, before
carrying out the measurement.
The figure resulting from the
measurement of the windings earth
resistance must be over 1Ω.
Figure 5.4.3 Earth Resistance
Should the figure be smaller than 1MΩ,
the windings must be adequately dried
up. This can be done by directing a
jet of hot air of about 50-60°C into
the generator air inlets or outlets.
Alternatively, the stator windings can
be electrically connected and a voltage
can be passed through them by means
of a DC power supply. The amount of
current in the windings depends on the
alternator size, even though it must be
fixed according to the nominal values
stated on the plate.
5.5 alternator
performanCe
It is recommend that users check the
alternator performance which must
comply with the data on the plate.
5.6 meCHanICal
InspeCtIons
It is recommend that users check all
fastening bolts and, in particular, the
electrical connections.
Special attention should be paid to all
electrical connections; this inspection
must be carried out in the complete
absence of voltage.
The setscrews retaining the alternator
to the engine must be checked to
ensure they are tight.