Mecc Alte ECO-ECP Série Manuel D'instruction Et De Maintenance page 17

Routine maintenance operations can be summed up as follows:
a) Assessment of windings conditions after long periods of stora-
ge or inactivity
b) Assessment, on a regular basis, of correct functioning
(absence of anomalous noises or vibrations)
c) Mechanical inspections on all fastening bolts and, in particular,
on electric connections
d) external cleaning of generator
a) Assessment of windings conditions after long pe-
riods of storage or inactivity.
Measuring the insulating earth resistance can assess the condi-
tion of the windings. This measurement can be carried out with a
"Megger" device, or similar, with a 500V direct-current voltage. It
is very important to disconnect the voltage regulator (fig. a), the
rotating diode bridge (fig. b) and the radio-interference filter (fig.
c), as well as 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 1MΩ.
Should the figure be smaller than the above mentioned one, the
windings must be adequately dried up. This can be done by direc-
ting a jet of hot air of about 50-60°C into the generator's air inlets
or outlets; alternatively, the stator's windings can be electrically
connected and a voltage can be passed through them by means
of a directcurrent power supply. The amount of current in the win-
dings depends on the generator size, even though it must be fixed
according to the nominal values stated on the plate.
b) Assessment of current functioning (absence of ano-
malous noises or vibrations).
We recommend users to check regularly the correct functioning of
the generator, and to verify that there are no anomalous noises or
vibrations; their presence might indicate damage of bearings.
May we remind you that the alternator itself has no particular vi-
bration since the rotating parts are perfectly balanced. Provided
that the rotor balancing has not been altered and that the rotor's
bearings have not been damaged, vibrations in the generator set
may occur due to alignments of couplings, due to stress upon the
combustion engine, or to vibration mounts.
We also recommend checking of performance data which must
comply with the data on the generator's plate.
ECO - ECP MANUAL
17
ENGLISH
MAINTENANCE
fig. a
fig. b
fig. c
ECO-ECP iMANUAL December 2013 Rev. 03