Sr.

No

Fault

Reasons

Remedial measures

1

Bent shape

Drawback in shaft coupling machine to
machine or machine to load shaft.

Due care during storage,
transportation must be taken.

2

Sparking between commutator and
brushes.

Brushes may not be touching to commutator
surfaces perfectly.

Adjust brush pressure of springs. Worn
out brushes be replaced by new ones. Proper shape may be given to brush by
grinding.

3

Snapped binding

Sometimes centrifugal force developed
on the armature winding is greater.

Take the proper measures.

4

Divergence in round shape of commutator

Commutator segments might not have
been properly pressed by tighting rings during assembling.

Load the machine properly. Check coupling.
Replace bearing. Stop machine if vibrations are excessive.

5

Trouble in bearings.

Lubrication, greasing, maintenance
scheduled not followed. Machine load coupling miss alignment. Excessive
vibrations due to sudden changes in load. Over loads for hours together.

Load the machine properly. Check
coupling. Replacing bearing. Stop machine if vibrations are excessive.

6

Mismatching of brush and brush
holders.

If holders are not proper as per the
brush sizes and spring tension is loose then vibrations are created.

Adjust properly.

7

Transformer

(1) Brushing developed cracks

Change in atmospheric condition too
cold, too hot, heavy rains affect the brushes. Electrostatic stress may cause
crack on brushing. This may also be due to pressure of connecting rod used
for connecting supply.

Maintenance scheduled must be followed
for clearing dust, dirt. Connection of supply line must be observed.

(2) Tap changer not working properly

Contact might have been damaged due
arcs developed due arcs developed when tap changer is used frequently on
load.

During breakdown maintenance, clean
the contact, remove carbon.

(3)damaged gaskets

Gasket makes the air tight seal of
tank containing oil in full level. Atmospheric conditions  and reaction of oil with gasket material
damages the gasket.

Replacement of gasket periodically.