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2019-05-24 / V1.0
Contactors C137/C163/C164/C165 – Installation and Maintenance Instructions
Maintenance
NOTICE
Detent-edged rings and detent-edged washers have
a limited life time. After 3 times opening of screws
secured with detent-edged rings or detent-edged
washers, the rings or washers must be replaced by
new ones.
X
Record the frequency of screw opening in the
work log.
X
After 3 times opening of screws, replace detent-
edged rings or detent-edged washers by new
ones.
Regular check activities
All of the maintenance activities that may be carried out
on the contactors by skilled personnel are listed below.
Component
Visual inspection
Measures
Cables/busbars
Check for:
X
broken cables, cable lugs
X
damaged insulation
X
kinks or crushing points
X
damaged busbars
X
loose or missing fastening elements
X
correct tightening torque of the terminal nuts
In case of faults:
X
immediately replace damaged cables
or cable lugs
X
immediately replace damaged bus-
bars
X
thighten loose fastening elements
immediately replace missing fasten-
ing elements
X
thighten the terminal nuts with the
rated torque
Contactor housing
Check for:
X
dirt
X
damage or wear and tear
X
loose or missing fastening elements
In case of faults:
X
remove existent dirt
X
if the contactor housing is damaged
replace the entire contactor
X
thighten a loose contactor housing
X
immediately replace missing fasten-
ing elements
Arc chamber
Check for:
X
damage or wear and tear
X
traces of burn-off (slightly sooting is acceptable)
In case of faults:
X
if the arc chamber ist damaged or
heavily worn replace the entire con-
tactor
Main contacts
(both fixed and
movable contacts)
The arc chamber cover has to be removed prior to
check the main contacts, see
“8.2 Preventive mainte-
nance“/ “Check the main contacts“.
Thereafter the main contacts are accessible and can
be checked for:
X
damage or wear and tear
X
traces of burn-off (slightly sooting is acceptable)
It requires some experience to evaluate the state
of the contacts. Even after only a few switchings
under load the contacts look used and “polluted”
for the inexperienced eye. The contactor needs
only be replaced if the loss of contact material is
more than 70%.
In case of faults:
X
if the loss of contact material is more
than 70%, replace the entire contac-
tor (minimum coating: 0.3 mm,
in new condition: 1.2 mm)