GE IAC57A - Page 7

Time
Overcurrent
Relays
Type
IAC
GEH
-
1753
The
current
-
closing
rating
of
the
contacts
is
30
amperes
for
voltages
not
exceeding
250
volts
.
The
current
-
carrying
ratings
are
affected
by
the
selection
of
the
tap
on
the
target
and
seal
-
in
coil
as
indicated
in
the
following
table
:
BURDENS
Burdens
for
the
standard
coils
are
given
in
the
following
table
.
These
are
calculated
burdens
at
five
amperes
based
on
burden
of
minimum
tap
.
Volt
-
ampere
burdens
for
the
lowest
tap
on
any
of
the three
coils
can
be
determined
for
any
value
of
current
,
up
to
20
times
tap
setting
,
from
Fig
.
3
.
DUAL
RATED
0.2
/
2.0
0.6
/
2.0
2.0
0.2
2.0
0.6
3.5
Carry
30
amps
for
(
sec
)
Carry
10
amps
for
(
sec
)
Carry
continuously
(
amp
)
Minimum
operating
(
amp
)
Minimum
dropout
DC
resistance
60
hertz
impedance
50
hertz
impedance
0.05
2.2
0.5
Coil
Amperes
Volt
-
Amps
Imp
.
Ohms
30
0.45
20
5.0
Freq
.
Tap
PF
0.37
2.3
1.2
2.6
0.2
2.0
0.6 2.0
4
-
16
60
4.0
(
amp
)
(
ohms
)
(
ohms
)
(
ohms
)
0.05 0.5
0.15
8.8
0.5
0.35
0.29
8.3
0.24 0.78
0.18
50
4.0
0.32
8.0
0.31
50
0.65
6.2
0.65
25
4.0
7.5
0.30
0.36
42
0.54
5.1 0.54
1.5
-
6.0
60
1.5
59.0
2.36
0.26
50
1.5
If
the
tripping
current
exceeds
30
amperes
,
an
auxiliary
relay
should
be
used
,
the
connections
being
such
that
the
tripping
current
does
not
pass
through
the
contacts
or
the
target
and
seal
-
in
coils
of
the
protective
relay
.
52.0
2.08
0.28
25
1.5
48.0
1.92
0.34
0.5
-
2.0
60
0.5
530.0
470.0
430.0
21.2
0.26
50
0.5
18.8
0.28
25
0.5
17.2
0.34
TA P
>
RAN G E
0. 5
-
2. 0
TAP
RA NG E
1. 5
-
6. 0
AMPS
.
TAP
RANGE
1
4
-
16
AMPS
.
MU L TI PL E S
OF
MI NI MU M
TA P
SE T TI NG
SA T UR AT I ON
CU R VE S
AT
VAR I OUS
FR E QU E NC I ES
FO R
3
TA P
RA N GE S
OF
THE TYPE
1
AC
51
A
REL A Y
LO W EST
TA P
US ED
IN
AL L
CA S ES
Fig
.
3
.
(
K
-
6306891
-
1
)
Saturation
Curves
for
Lowest
Taps
of
the
Induction
Unit
of
Type
IAC
Relays
with
Inverse
-
time
Characteristics
.
5
Courtesy of NationalSwitchgear.com