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busbars consist of 10 layers of pre-shaped sheet copper. This construction is able
to compensate for small changes in length caused by temperature rise when
current is flowing. The screw fixings between heatsink and flexible copper busbar
have to withstand different types of mechanical stress. Therefore each fixing needs
to be checked for correct torque. This check should be done regularly, e.g.
annually or together with all the other work to be done for preventive maintenance.
Actions:
−
Make sure all supply voltages are switched off, most important the supply for
the power part (armature), for the electronic power part (SDCS-POW-4
respectively SDCS-POW-1), for the converter fan and for other auxiliaries!
−
Open the cabinet’s and module’s door; if needed secure them.
−
Set a latching torque spanner to 25 Nm (18 lb-ft); a 17 mm nut is needed too.
−
Check the torque of the screws marked within
.
−
Apply the torque spanner to the screw and turn right until the right torque is
indicated.
−
Don’t loosen the screws by a left hand turn!
−
Put on a new marking, if appropriate.
Relays and electrical connections
Relays should be checked for proper function and all connections should be
inspected and checked for tightness. Any signs of corrosion, especially at ground
components, must be removed.
Preventive Maintenance
3ADW000352R0101 DCS800-A Installation Manual e a
