Repair On Switchgear Assemblies; Repair Of Surface Damage - ABB UniGear ZS1 Installation, Operation And Maintenance Instructions Manual

M A I N T E N A N C E
8.3 Inspection
• Where necessary, the working area must be
isolated and secured against reconnection in
accordance with the safety regulations specified
by IEC and any appropriate national standards
before inspection
• Correct switchgear functionalities should be
monitored by regular inspections
• Under normal operating conditions, inspection
should be carried out once every four years
by specially trained professional electricians
• Under abnormal operating conditions (including
adverse climatic conditions) and/or special
environmental stresses (heavy pollution and
an aggressive atmosphere among others), the
frequency of inspection may have to be increased
• Inspection is primarily to carry out a visual check
for grime, corrosion and moisture:
- Effects of high temperature on the main
circuits
- Traces of partial discharge on the insulating
material parts
- Traces of leakage current on the insulating
material parts
- Surfaces of the contact systems
• However, inspection must also include correct
mechanical/electrical operation of the following
parts: switching devices, actuating, interlocking,
protection and signalling devices
Caution
With regard to the switching devices,
their separate Instruction manual should
be followed.
8.4 Servicing
When, during an inspection, the need to carry
out cleaning operations is noted, proceed as
follows:
• Clean the surfaces:
- Remove any dry dust deposits which are not
very adherent using a soft dry cloth
- Remove any more adhering dirt with ethanol
F 25 M
• Clean the insulating surfaces and the conductive
components with ethanol F 25 M
• After cleaning, rinse with clean water and dry
carefully
• Should any partial discharges occur as a
consequence of the condensation phenomenon,
a temporary remedy which is often effective
is application of a thin layer of silicone over
the surface involved. For a permanent remedy
to this type of unusual problem, contact the
ABB service department
8.5 Repair

8.5.1 Repair on switchgear assemblies

8.5.1.1 Repair of surface damage

• Carry out repair work immediately after a
defect has been discovered
• Completely remove all rust from damaged
paintwork areas on steel sheet and other
steel parts by mechanical means, e.g. with a
wire brush
• Lightly grind the surrounding paint coat and
carefully degrease the entire area. Then
immediately apply an anti-rust primer and, after
an appropriate hardening time, apply the top
coat. Only use suitable and compatible paint
products
• Apply the top coat in standard RAL7035 colour,
or the relevant special colour
• Carefully remove any white rust on aluminium/
zinc surfaces with a wire brush or cleaning pad,
e.g. Scotch-Brite, and clean loosely adhering
particles with a dry, non-fraying cloth. Next
treat the cleaned parts with zinc spray or zinc
powder paint and, finally, treat with aluminium
spray for colour matching
• Carefully remove any white rust from passivated
operating parts and rust formation on
phosphatised parts with a wire brush or
metal-free cleaning pad, e.g. Scotch-Brite, and
clean with a dry cloth. Then grease evenly (with
mechanical grease for moving parts)
Remove the contact system and thoroughly clean.
Note:
The set installation position of the contact arms
must not be changed by undue use of force.
Replace the contact pins when the surface has
been damaged. Replaced pins should be
retightened using socket head bolts.
8.5.1.2 Repair on earthing switch signaling
contact
The auxiliary switches of the interchangeable
groups are adjusted at the factory.
When final installation of the earthing switch and
operator takes place on site, it may be necessary to
carry out further precise adjustment of the auxiliary
switch. In this case, the following should be taken
into account:
• There must be a run-on of 0.5 mm in the fully
operated position before the plunger reaches
the stop position (for safety reasons)
• The auxiliary limit switch for earthing switch
ON must be operated immediately after the
toggle spring mechanism is precisely centered
in the closing process and the automatic rapid
closing process has started
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