GE IAC57A - Page 16

GEH
-
1753
Time
Overcurrent
Relays
Type
IAC
CONTACT
CLEANING
and
deterioration
of
the
contacts
.
Abrasive
paper
or
cloth
may
leave
minute
particles
of
insulating
abrasive
material
in
the
contacts
and
thus
prevent
closing
.
For
cleaning
fine
silver
contacts
,
a
flexible
burnishing
tool should
be
used
.
This
consists
of
a
flexible
strip
of
metal
with
an
etched
roughened
surface
,
resembling
in
effect
a
superfine
file
.
The
polishing
action
is
so
delicate
that
no
scratches
are
left
,
yet
corroded
material
will be
removed
rapidly
and
thoroughly
.
The
flexibility
of
the
tool
insures
the
cleaning
of
the
actual
points
of
contact
.
Fine
silver
contacts
should
not
be
cleaned
with
knives
,
files
,
or
abrasive
paper
or
cloth
.
Knives
or
files
may
leave
scratches
which
increase
arcing
The
burnishing
tool
described
above
can
be
obtained
from
the
factory
.
PERIODIC
TESTING
An
operation
test
and
inspection
of
the
relay
at
least
once
every
six
months
are
recommended
.
Test
connections
are
shown
in
Fig
.
18
.
RENEWAL
PARTS
It
is
recommended
that
sufficient
quantities
of
renewal
parts
be
carried
in
stock
to
enable
the
prompt
replacement
of
any
that
are
worn
,
broken
,
or
damaged
.
When
ordering
renewal
parts
,
address
the
nearest
Sales
Office
of
the
General
Electric
Com
-
pany
,
specify
quantity
required
,
name
of
part
wanted
,
and
give
complete
nameplate
data
.
If
possible
,
give
the
General
Electric
Company
requisition
number
on
which
the
relay
was
furnished
.
For
a
recommended
parts
list
refer
to
Parts
Bulletin
number
GEF
-
3883
.
rtt
SEI
94
JC
RATH
)
INSTJNTMOUS
WIT
OPERATING
TIME
.
025
*
.
010
Q
-
.
005
10
9
8
7
6
5
4
3
1.5
2
MULTI
PIES
OF
PICKUP
Fig
.
19
(
0208
A
8695
(
\
}
)
Time
-
Current
Characteristics
for
the
"
Hi
-
G
"
Unit
Since
the
last
edition
,
Figures
12
and
14
have been
revised
.
14
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