ABB UniGear 500R - Maintenance and Servicing Schedule

64
9. Maintenance
WARNING
For ENA version: do not access the area behind or
alongside the switchgear when it is energised or
being energised.
9.1 General
Maintenance serves to preserve trouble-free operation
and achieve the longest possible working life of the
switchgear. It comprises the following closely related
activities:
Inspection: Determination of the actual condition
Servicing: Measures to preserve the specified
condition
Repair: Measures to restore the specified condition
Note: When carrying out all maintenance work, the
regulations in the country of installation must be
strictly complied with. Maintenance work may only be
performed in a careful manner by qualified competent
personnel familiar with the characteristics of the
individual switchgear, in accordance with all relevant
IEC safety regulations and those of other technical
authorities, and with other overriding instructions. It is
recommended that ABB service personnel be called in
to perform the servicing and repair work detailed
below. The inspection and servicing intervals for some
of the equipment/components (e.g. parts subjects to
wear) are determined by fixed criteria, such as
switching frequency, length of service and number of
short-circuit breaking operations. On the other hand,
for other parts the length of the intervals may depend,
for example, on the different modes of operation in
individual cases, the degree of loading, and also
environmental influences (including pollution and
aggressive air). The operating instructions of Vmax
circuit-breaker must also be followed.
If necessary, further details can be taken from the
technical documentation for the switchgear installation
(including, for example, any special operating
conditions agreed on).
9.1.1 Intervals for inspection, servicing and repairs
Time intervals for maintenance work to be carried out
always depend on the operating conditions of the
switchgear, and mainly on the mode of operation, the
number of rated and short-circuit current switching
operations, ambient temperature, pollution etc. We
recommend carrying out the maintenance work at the
following intervals:
Activity performed
According to section
Time interval in years
According to number of switching operations
Inspection
9.2
4
(1)
As required
(3 )
Servicing
9.3
4
(2)
As required
(3 )
Repair
9.4
As required
As required
(1) In more demanding service conditions , we recommend reducing this interval suitably
(2) According to the results of the inspection.
(3) See the instruction manuals of the switching device.
9.2 Inspection
 Where necessary, the working area must be
isolated and secured against reconnection in
accordance with the Safety Regulations specified
by IEC and appropriate national standards before
inspection.
 Correct condition of the switchgear should be
monitored by regular inspections.
 Under normal operating conditions, inspection
should be carried out once every four years by
qualified competent electricians.
 Under abnormal operating conditions (including
adverse climatic conditions) and/or special
environmental stresses (heavy pollution and
aggressive atmosphere, among others), inspection
may be necessary at shorter intervals.
 Inspection is primarily to carry out a visual check
for grime, corrosion and moisture:
-Effects of high temperature on 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.
 With regard to the switching devices, their
separate Instruction manual should be followed
 Check all switchgear accessories and auxiliary
devices (e.g. storage batteries).
 No partial discharge must occur on the surfaces of
equipment at operating voltage. This can, for
example, be detected by characteristic noises, a
clearly perceptible smell of ozone, or visible
glowing in the dark.
 Visually checking the contact system. We
recommend turning the contact system alternately
in order to clean the inner contact points of the
contact system. The contact points should be
cleaned if signs of overheating (discoloured
surface) are visible.
 If any irregular conditions are detected, then
relative repair measures must be taken.