23
SIVACON S4 - ALPHA
Switchboard maintenance cycle
Tightening torque
Fastening
screw
Bus-bar/
fairlead
Bus-bar/
bus-bar
M5
3 Nm
5 Nm
M6
5 Nm
8 Nm
M8
11 Nm
20 Nm
M10
22 Nm
40 Nm
M12
40 Nm
70 Nm
All described procedures aim to ensure
assembly start-up.
When the switchboard begins to work,
it is necessary to plan a number of
scheduled maintenance activities,
at regular intervals. This procedure
guarantees safety and reliability levels,
and reduces repairs and downtimes.
For optimal panel utilization,
maintenance cycles must be observed
rigorously.
Structure of the board and frame
The operations that follow mostly of
consist of a careful visual examination
to inspect for the presence of animals
or bugs, in addition assessing the
functionality of the doors, hinged
covers, etc.
These checks must be performed
on each compartments.
Maintenance cycle
• Making sure tightened screws
and bolts
(
Operation to be performed twice
yearly)
• Cleaning all metal parts with clean
rags, without liquids
(
Operation to be performed twice
yearly)
• Cooling fins and grids must be cleaned
regularly to prevent them from clogging.
(
Operation to be performed twice
yearly).
Bus-bar systems and connections
The bus-bar systems and connections
must also be checked regularly and
cleaned with dry and clean rags.
• Visual examination of bus-bars and
insulators conditions
• Insulation resistance measure among
phases and between phases and ground,
after cleaning the bus-bars and their
supporting parts with dry rags.
This test must be performed in according
to CEI EN 61439-1, paragraph 11.9 and
the minimum value measured must
be 1000 Ω; where the voltage is the
nominal value on the ground side.
• Continuity protection circuit, including
metal part connection, such as doors
and panels, carriages, metal parts
of devices.
• Checking correct tightening of
connections with a torque.
The relative torque is specified in the
table
as a function of type of junction used.
For terminal strips, checking the
tightening of connections on the panel
and the system side.
For terminals with leads up to 35 mm
2
, it
should be verified the correct tightening
according to the torque that can be
worked out from the values listed in the
catalogues.
For safety reasons, these operations
must be performed with the power off
(
Operations to be performed twice
yearly).
ITA
ENG
