Advertisement
Table
4
.
Check Points for
Inspection
( cont
.
)
5
>
Check Point
No
Check Item
Check Method
Criteria
What
to
do
Remarks
z
2
Closing and
tripping shaft
Operating
Mechanism
and Safety
Devices
Visual
check .
Must
rotate
smoothly .
Apply a small
amount
of
machine oil
.
m
>
Z
Interlock
,
key
-
switches
,
etc
.
Must
operate
smoothly
,
securely
,
and properly
.
Functional
check
.
Reinstate
to
proper operating
condition
.
o
m
3
Vacuum
Interrupter
Contact wear
Measurement
of wipe
length
.
Wipe length
should
be
greater
than
1
mm
(
. 039
in .
)
Pg .
36
Factory service
is
required if the
wipe length is 1
mm .
(
.
039
in
.
)
or
less
.
Vacuum
pressure
See Vacuum Check section
Factory
service
required when
vacuum
pressure
is
not
sufficient .
Pg
.
37
Number of
open -
close
operations
Counter
.
When the
counter
reading
reaches
6
,
000 or
6 years
of
service has
been reached
(
for the rated
current
interruption
) ,
check the internal
pressure
.
Follow up checks should
be made every 3 years of service
thereafter or until the
counter
reading reaches 10
,
000
.
For the
method of checking the vacuum
pressure
see
the Vacuum Check
section
.
Factory
service
is required if the
internal pressure
is
not
sufficient
or when the
counter
reaches
10
,
000
.
Pg
.
37
Contamination
Visual check
.
There should be no dust or
foreign
matter
on the
interrupter surface
.
Wipe with a
clean cloth
dampened
with
alcohol
.
-
o
»
<
Q
<
D
(
A
)
(
A
)
Advertisement
