ABB UniGear 500R - Page 68

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9.3.1.3 Cleaning the kinematics and the main
contacts
 Carry out a visual inspection of the mechanical
connections and check for any presence of dirt,
humidity and signs of corrosion on the main
operating shaft and on the contact parts of the
blades.
 Remove any deposits of dust using a dry cloth that
does not leave any deposits on the treated
surfaces (do not use woollen cloths).
 If necessary, grease the moving mechanical parts
by applying a thin layer of mechanical grease for
moving parts.
9.3.1.4 Cleaning, greasing and checking the
kinematics
 Carry out a visual inspection of the kinematics and
check for any presence of dirt, humidity and signs
of corrosion on the moving parts.
 Remove any deposits of dust using a dry cloth that
does not leave any deposits on the treated
surfaces (do not use woollen cloths).
 If necessary, grease the mechanical moving parts
by applying a thin layer of mechanical grease for
moving parts.
9.3.1.5 Reaching mechanical life limit
 The mechanical life of the three position
disconnector is set at 2000 opening/closing
operations. After the operation counter has
reached this number, inform ABB who will verify
directly that the mechanical life limit of the
earthing switch has been reached.
 Lubrication of fixed and movable contacts of three
position disconnector by applying a thin layer of
grease for electrical contacts must be done after
600, 1000, 1300 and 1600 opening/closing
operations.
Note: The operation counter is not provided with the
switchgear. It is up to the engineering department to
connect the auxiliary closed/open contacts in order to
measure the number of operations carried out.
9.3.1.6 Cleaning and checking of the current
transformers
 Make the plant you want to work on safe (follow
the plant safety regulations).
 Visually check the connections of the current
transformers.
 Using a dynamometric spanner, check the
tightness of all the screws (see table) in paragraph
6.3.
9.3.1.7 Cleaning and checking of the voltage
transformers
a) Rear voltage transformers
 Make the plant you want to work on safe (follow
the plant safety regulations).
 Visually check the voltage transformer
connections.
 Using a dynamometric spanner check tightness of
all the screws (see table) in paragraph 6.3.
 Carry out a visual inspection of the transformers
and check for any presence of dirt.
 Remove any deposits of dust using a dry cloth that
does not leave any deposits on the treated
surfaces (do not use woollen cloths).
b) Front voltage transformers
 Make the plant you want to work on safe (follow
the plant safety regulations).
 Follow procedure described in chapter 9 in order to
have access to front voltage transformers and to
its fuses (if any).
 Visually check the voltage transformer
connections.
 Using a dynamometric spanner check tightness of
all the screws (see table) in paragraph 6.3.
 Carry out a visual inspection of the transformers
and fuses (if any) and check for any presence of
dirt.
 Remove any deposits of dust using a dry cloth that
does not leave any deposits on the treated
surfaces (do not use woollen cloths).