Nilfisk-Advance SR 1700 2WD B Betriebsanleitung Seite 59

Drive direct current motor
Maintenance
Commutator Ensure that the surface along which the carbon
brushes slide is covered with an even, shiny,
transparent light grey film.
Check that there are no black marks or burns
between the commutator segments and on the
commutator outer crown.
Ensure that the commutator surface is not lined,
deeply grooved or burnt on the segment in or out
edges.
Check that the brooms have not grooved the
commutator surface and that the insulating mica
does not protrude from the copper segment.
Check that the commutator is clean and that there
are no burns on the segments; if necessary, clean
the commutator as described.
Check eccentricity.
Clean the commutator with special rubber sticks. If
necessary, clean between the segments.
Carbon Check the carbon brush for wear. It is worn out
brushes when more than half of its total length has been
consumed. Check that it slides freely in the brush
holder, that it is pressed correctly by the spring and
that the spring is still elastic.
Ensure that the surface along which the carbon
brushes slide is evenly and highly polished and
that any lines or porosity are extremely small and
of similar dimensions.
Check the wire for wear and ensure that the
connection terminals are well tightened.
Ensure that there are no big lines, deep grooves,
craters, burns or splinters on the carbon brush
edge and that all the carbon brushes are worn in
the same way.
Check the housing for wear and clearance.
Brushes usually last from 6 months to 1 year,
depending on use.
Check the carbon brush and coupling pressure.
When the warning light turns on, the carbon
brushes need to be replaced, even if 300 hours
have not been reached.
Terminals Check that supply bolt nuts are well tightened and
that the insulating materials are in good condition.
Fan Ensure that air intakes are not clogged and that the
fan turns freely.
Bearings Check the temperature and the vibration and noise
degree.
Insulation Use a megger, especially when the environment is
wet, to check the insulation value: it should never
be less than 2 MOhm.
Screws Check that the screws are not loose.
Check that there are no faulty contacts in the
electrical connections which could lead to local
overheating.
Windings General cleaning. Check that the insulation to
ground is less than 2 MOhm.
33014816(1)2005-07 A
Every 150 Every 200 Every 400
hours hours hours
USER MANUAL
Every time
Every 6 Every
a check is
months year
carried out
15