GE CEX57D User manual
GEK
-
49778
CONTENTS
PAGE
DESCRIPTION
APPLICATION
CEX
57
D
AND
CEX
57
F
CEX
57
E
RATINGS
CONTACTS
OPERATING
PRINCIPLES
CHARACTERISTICS
ANGLE
-
IMPEDANCE
UNIT
UPPER
UNIT
LOWER
UNIT
TAPPED
AUTOTRANSFORMER
BURDENS
CURRENT
CIRCUIT
POTENTIAL
CIRCUIT
CALCULATION
OF
SETTINGS
rflNCTRlirTTON
RECEIVING
,
HANDLING
AND
STORAGE
ACCEPTANCE
TESTS
VISUAL
INSPECTION
MECHANICAL
INSPECTION
ELECTRICAL
TESTS
ELECTRICAL
TESTS
-
AUXILIARY
UNIT
(
CEX
57
F
ONLY
)
INSTALLATION
PROCEDURE
LOCATION
MOUNTING
CONNECTIONS
VISUAL
INSPECTION
MECHANICAL
INSPECTION
INSPECTION
ANGLE
-
IMPEDANCE
TESTS
PERIODIC
CHECKS
AND
ROUTINE
MAINTENANCE
CONTACT
CLEANING
SERVICING
CONTROL
SPRING
ADjuSTMENT
*
.
*
.
!
!
!
.
.
ANGLE
OF
MAXIMUM
TORQUE
ADJUSTMENT
BASIC
REACH
OHMS
CORE
ADJUSTMENT
RENEWAL
PARTS
3
3
3
4
4
4
4
6
6
6
7
7
8
8
8
9
10
11
12
12
12
12
OHM
UNIT
13
14
14
14
14
14
14
14
14
15
15
16
16
16
17
18
18
(
COVER
PHOTO
8042958
)
2
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GEK
-
49778
ANGLE
-
IMPEDANCE
RELAY
TYPES
:
CEX
57
D
CEX
57
E
CEX
57
F
DESCRIPTION
Type
CEX
57
relays
are
high
speed
induction
cup
-
type
devices
with
ohm
unit
characteristics
that
can
be
set
parallel
to
the
impedance
of
a
transmission
line
.
The
relays
are
designed
for
use
with
other
protective
devices
in
blinder
applications
to
restrict
the
tripping
area
of
the
tripping
units
used
in
a
protective
relay
scheme
.
Or
,
they
may
be
used
in
applications
where
tripping
is
required
during
an
out
-
of
-
step
condition
.
instruction
book
.
These
applications
are
discussed
in
the
APPLICATION
section
of
this
Type
CEX
57
relays
each
contain
two
cup
-
type
units
,
and
they
are
mounted
in
an
M
2
size
case
.
The
CEX
57
F
relay
also
contains
an
auxiliary
telephone
-
type
unit
.
Internal
connections
for
the
relays
are
shown
in
Figures
9
,
10
and
11
;
typical
external
connections
are
shown
in
Figure
5
.
Outline
and
panel
drilling
dimensions
are
shown
in
Figure
14
.
APPLICATION
The
CEX
57
relays
were
designed
specifically
for
use
in
blinder
applications
,
or
in
applications
to
initiate
tripping
during
an
out
-
of
-
step
condition
.
Three
models
of
the
relay
are
available
:
CEX
57
D
,
CEX
57
E
and
CEX
57
F
.
Typical
applications
for
each
of
these
relays
are
as
follows
:
CEX
57
D
AND
CEX
57
F
The
CEX
57
D
and
CEX
57
F
relays
are
used
in
blinder
applications
to
restrict
the
area
of
the
tripping
functions
used
in
a
transmission
line
protective
relaying
scheme
(
see
Figure
4
)
.
Either
three
CEX
57
D
or
three
CEX
57
F
relays
are
required
.
Basically
,
tripping
will
be
permitted
only
when
the
fault
impedance
plots
within
the
reach
of
the
mho
tripping
function
AND
both
of
the
ohm
units
.
Since
the
right
hand
ohm
unit
will
operate
only
for
faults
to
the
left
of
it
,
both
units
can
operate
simultaneously
only
for
faults
that
plot
between
them
.
The
tripping
function
(
mho
)
will
provide
correct
directional
action
,
and
limit
the
reach
in
the
forward
direction
.
The
contacts
of
the
CEX
57
D
ohm
units
are
brought
out
separately
,
and
are
externally
connected
in
series
with
the
contacts
of
the
corresponding
mho
tripping
function
to
provide
supervision
(
see
Figure
5
C
)
.
The
contacts
of
the
CEX
57
F
relay
are
These
instructions
do
not
purport
to
cover
all
details
or
variations
in
equipment
nor
to
provide
for
every
possible
contingency
to
be
met
in
connection
with
installation
,
operation
or
maintenance
.
Should
further
information
be
desired
or
should
particular
problems
arise
which
are
not
covered
sufficiently
for
the
matter
should
be
referred
to
the
General
Electric
Company
.
the
purchaser
'
s
purposes
.
To
the
extent
reguired
the
products
described
herein
meet
applicable
ANSI
,
but
no
such
assurance
is
given
with
respect
to
local
codes
and
ordinances
because
they
vary
greatly
.
IEEE
and
NEMA
standards
;
3
Courtesy of NationalSwitchgear.com
GEK
-
49778
internally
connected
in
series
,
and
are
used
to
operate
the
internal
mounted
auxiliary
telephone
relay
.
The
contacts
of
this
auxiliary
relay
are
then
used
to
supervise
the
corresponding
mho
tripping
function
(
see
Figure
5
B
)
.
CEX
57
E
The
Type
CEX
57
E
relay
was
designed
specifically
for
use
with
Type
GSY
or
NAA
relays
,
which
provide
the
additional
functions
required
to
implement
an
out
-
of
-
step
tripping
scheme
.
Only
one
CEX
57
E
relay
is
required
in
these
applications
.
The
CEX
-
NAA
combination
is
primarily
for
application
to
transmission
lines
,
combination
is
primarily
for
application
to
generators
.
Specific
details
on
the
operation
of
either
of
these
schemes
can
be
found
in
the
appropriate
NAA
or
GSY
relay
instruction
books
.
For
further
information
,
and
exact
model
numbers
of
these
relays
,
contact
the
nearest
General
Electric
District
Sales
Office
.
The
CEX
-
GSY
RATINGS
The
Type
CEX
57
relays
covered
by
these
instructions
are
rated
120
volts
,
five
amperes
,
for
either
50
or
60
hertz
.
They
have
three
basic
minimum
ohmic
reaches
that
are
set
by
a
double
set
of
taps
on
each
unit
.
The
taps
are
0.5
,
1.5
or
3.0
ohms
(
phase
-
to
-
nuetral
)
when
the
maximum
torque
angle
is
set
for
five
degrees
lead
(
current
leads
voltage
)
.
The
reach
of
the
unit
can
be
increased
from
minimum
ohms
(
100
percent
tap
)
to
ten
time
the
minimum
ohms
(
ten
percent
tap
)
by
means
of
taps
in
the
potential
circuit
.
The
relay
can
be
set
for
an
ohmic
reach
between
0.5
ohms
and
30
ohms
.
TABLE
I
TAP
RANGE
IN
RANGE
IN
AMPERES
ONE
SECOND
CURRENT
RATING
CONTINUOUS
CURRENT
RATING
USED
OHMS
0.5 0.5
-
5
8.2
-
40
100
amperes
100
amperes
5
amperes
1.5
1.5
-
15
5.0
-
40
5
amperes
3.0
3.0
-
30
3.5
-
40
100
amperes
5
amperes
CONTACTS
The
contacts
of
the
Type
CEX
57
relay
will
close
and
carry
30
amperes
DC
momentarily
.
However
,
the
circuit
breaker
trip
circuit
must
be
opened
by
an
auxiliary
switch
contact
or
other
suitable
means
,
since
the
relay
contacts
have
no
interrupting
rating
.
OPERATING
PRINCIPLES
The
units
in
the
Type
CEX
57
relay
are
four
-
pole
induction
cylinder
units
(
see
Figure
2
)
,
with
schematic
connections
as
shown
in
Figure
6
.
impedance
at
an
angle
.
The
two
front
coils
and
the
two
back
coils
are
energized
with
These
units
measure
4
Courtesy of NationalSwitchgear.com
GEK
-
49778
delta
currents
to
produce
polarizing
flux
.
The
same
delta
current
flows
through
the
operating
coil
to
produce
an
operating
flux
.
The
phase
-
to
-
phase
voltage
is
applied
to
the
restraint
coil
to
produce
a
restraint
flux
.
The
torque
produced
by
the
unit
results
from
the
interaction
of
the
fluxes
.
The
torque
,
therefore
,
is
as
shown
below
:
TR
Torque
=
I
x
I
x
Tg
-
I
x
E
x
x
cos
(
0
-
9
)
100
I
=
delta
current
(
I
/
\
-
Ig
)
TB
=
basic
reach
tap
E
=
phase
-
phase
voltage
(
E
/
\
B
)
TR
=
restraint
tap
in
percent
0
=
angle
between
(
1
^
-
Ig
)
and
E
^
B
0
=
maximum
torque
angle
of
the
relay
At
the
relay
balance
point
,
the
torque
is
zero
.
where
:
TR
0
=
I
x
I
x
TB
-
I
x
E
x
X
cos
(
0
-
0
)
100
TR
x
cos
(
0
-
0
)
=
I
X
I
x
TB
=
I
x
E
x
100
TR
x
cos
(
0
-
0
)
=
I
x
TB
=
E
x
-
cos
(
0
-
0
)
=
-
5
-
x
100
100
I
TR
The
phase
-
to
-
phase
voltage
(
E
)
divided
by
the
delta
current
is
equal
to
the
phase
-
to
-
neutral
ohms
(
Z
)
.
Therefore
:
Z
cos
(
0
-
0
)
=
^
x
100
TR
For
example
,
if
the
basic
reach
taps
(
TB
)
are
set
for
1.5
ohms
,
and
the
restraint
tap
(
TR
)
is
set
for
50
percent
,
then
the
relay
reach
(
Z
)
will
be
:
x
100
=
3
ohms
(
phase
-
to
-
neutral
)
1.5
Z
cos
(
0
-
9
)
=
50
The
equation
,
TB
Z
cos
(
0
-
9
)
=
x
100
TR
is
the
equation
for
a
straight
line
when
plotted
on
an
R
-
X
diagram
(
Figure
3
)
.
The
equation
also
gives
a
straight
line
if
Z
and
0
are
plotted
on
polar
paper
(
Figure
4
)
.
5
Courtesy of NationalSwitchgear.com
GEK
-
49778
By
selecting
values
for
TB
and
TR
,
the
characteristic
can
be
adjusted
to
be
at
any
distance
from
0.5
to
30
ohms
from
the
origin
.
This
30
ohm
limitation
is
based
on
TR
never
being
less
than
ten
percent
,
its
minimum
recommended
value
.
The
angle
of
maximum
torque
(
0
)
can
be
adjusted
to
be
any
angle
between
5
degrees
lead
and
35
degrees
lead
for
the
top
unit
.
The
bottom
is
identical
to
the
top
unit
,
except
its
polarity
is
reversed
so
that
the
maximum
torque
angle
is
adjustable
from
5
plus
180
,
or
185
degrees
,
to
35
plus
180
,
or
215
degrees
.
The
upper
potentiometer
on
each
unit
(
PI
for
the
upper
unit
and
P
2
for
the
lower
unit
)
is
used
to
set
the
angle
of
maximum
torque
.
With
the
potentiometer
set
for
zero
ohms
,
the
angle
of
maximum
torque
will
be
between
25
and
30
degrees
(
current
leads
voltage
)
.
If
a
jumper
is
added
to
connect
stud
13
to
stud
14
,
and
a
second
jumper
to
connect
stud
15
to
stud
16
,
then
the
angle
of
maximum
torque
can
be
adjusted
to
be
between
5
degrees
and
25
degrees
by
using
the
PI
potentiometer
for
the
upper
unit
,
and
the
P
2
potentiometer
for
the
lower
unit
.
If
jumpers
are
not
added
,
then
these
same
two
potentiometers
(
PI
for
the
upper
unit
and
P
2
for
the
lower
unit
)
can
be
used
to
adjust
the
angle
of
maximum
torque
to
be
between
30
and
35
degrees
.
Angle
of
maximum
torque
can
be
set
between
25
and
30
degrees
using
these
same
two
potentiometers
,
jumpers
should
be
added
or
not
will
vary
from
relay
to
relay
,
and
will
have
to
be
determined
by
test
of
the
relay
actually
being
adjusted
.
Whether
the
CHARACTERISTICS
ANGLE
-
IMPEDANCE
UNIT
The
angle
-
impedance
unit
characteristic
is
a
straight
line
when
plotted
on
an
R
-
X
diagram
.
The
shortest
distance
from
the
characteristic
to
the
origin
is
the
minimum
relay
reach
.
The
minimum
relay
reach
is
determined
by
two
sets
of
taps
.
The
two
tap
plugs
in
the
current
circuits
set
the
basic
minimum
reach
(
TB
)
.
The
tap
plugs
in
the
restraint
circuit
increase
the
basic
reach
as
the
restraint
taps
(
TR
)
are
reduced
from
100
percent
.
The
reach
at
angle
of
maximum
torque
is
equal
,
therefore
,
to
:
TB
x
100
ZM
=
-
TR
ZM
=
minimum
reach
TB
=
minimum
basic
reach
TR
=
restraint
tap
where
:
UPPER
UNIT
The
angle
of
maximum
torque
is
the
angle
that
the
reach
,
Z
^
,
described
above
,
leads
the
"
R
"
axis
(
Figure
4
)
.
This
angle
is
adjustable
from
5
to
35
degrees
lead
.
The
reach
of
the
angle
-
impedance
unit
at
any
angle
is
given
by
the
following
equation
:
tB
x
100
TR
x
cos
(
0
-
0
)
cos
(
0
-
0
)
ZM
Z
=
6
Courtesy of NationalSwitchgear.com
GEK
-
49778
0
=
angle
I
/
\
g
leads
V
/\
g
0
=
angle
of
maximum
torque
See
Table
II
for
values
of
Tg
for
the
various
angles
of
maximum
torque
.
where
:
LOWER
UNIT
This
unit
is
identical
to
the
upper
unit
except
it
is
polarized
to
have
maximum
torque
180
degrees
from
the
upper
unit
.
Therefore
,
the
equation
is
:
ZM
Z
=
cos
(
0
-
9
+
180
)
The
value
Tg
is
given
in
Table
II
for
various
angles
of
maximum
torque
.
The
value
of
TB
is
equal
to
the
tap
value
when
the
maximum
torque
angle
is
set
for
five
degrees
.
If
only
the
upper
potentiometer
(
PI
for
the
upper
unit
,
or
P
2
for
the
lower
unit
)
is
adjusted
,
the
value
of
TR
will
be
as
shown
in
Table
II
.
The
value
of
Tg
can
be
adjusted
by
using
the
lower
potentiometer
(
P
3
for
the
upper
unit
,
or
P
4
for
the
lower
unit
)
;
however
,
it
may
not
be
possible
to
make
Tg
equal
to
the
tap
value
at
all
angles
of
maximum
torque
settings
.
TABLE
II
BASIC
REACH
OHMS
(
TB
)
ANGLE
OF
MAXIMUM
TORQUE
STUDS
13
-
14
STUDS
15
-
16
0.5
OHM
TAP
1.5
OHM
TAP
3.0
OHM
TAP
50
Jumper
1.43
-
1.58
2.85
-
3.15
0.48
-
0.53
10
°
Jumper
0.41
-
0.47
1.22
-
1.40
2.43
-
2.79
15
°
Jumper
1.14
-
1.26
0.38
-
0.42
2.28
-
2.52
20
°
Jumper
0.34
-
0.38
1.02
-
1.13
2.04
-
2.25
25
°
Jumper
0.94
-
1.07
1.89
-
2.13
0.32
-
0.36
30
°
Open
0.31
-
0.37
0.92
-
1.11
1.83
-
2.22
350
Open
0.35
-
0.40
1.05
-
1.20
2.10
-
2.40
TAPPED
AUTOTRANSFORMER
The
reach
in
ohms
of
the
angle
-
impedance
may
be
adjusted
by
two
taps
on
the
autotransformer
.
The
tap
block
and
the
tap
plugs
are
located
on
the
right
side
of
the
relay
.
The
two
tap
leads
marked
#
1
control
the
upper
unit
,
and
the
two
tap
leads
marked
#
2
control
the
lower
unit
.
The
upper
#
1
and
#
2
tap
leads
should
be
connected
to
a
tap
in
the
upper
half
of
the
block
(
zero
to
ten
percent
)
.
The
lower
#
1
and
#
2
tap
leads
should
be
connected
to
a
tap
in
the
lower
half
of
the
block
(
10
to
90
percent
)
.
The
restraint
tap
setting
,
TR
,
is
the
sum
of
the
two
tap
values
into
which
the
#
1
or
#
2
leads
7
Courtesy of NationalSwitchgear.com
GEK
-
49778
are
connected
.
For
example
,
if
the
upper
#
1
lead
is
put
in
the
5
tap
,
and
the
lower
#
1
lead
is
put
in
the
60
tap
,
then
the
#
1
tap
setting
,
TR
is
5
plus
60
,
or
65
.
TR
should
not
be
set
for
less
than
ten
percent
.
BURDENS
CURRENT
CIRCUIT
The
current
burden
imposed
by
each
current
circuit
at
five
amperes
is
listed
in
Table
III
.
TABLE
III
BASIC
OHM
TAP
AMPS
HERTZ
R
X
PF
WATTS
VA
5
60
0.5
0.10
0.09
0.72
2.41
3.35
5
60
1.5
0.12
0.10
0.77
3.06
3.95
5
60
3.0
0.16
4.11
5.13
0.12
0.80
5
50
0.5
0.09
2.14
0.08
0.74
2.89
5
50
1.5
0.11
0.08
0.80
2.75
3.45
5
50
3.0
0.14
0.10
0.81
3.59
4.41
POTENTIAL
CIRCUIT
The
maximum
potential
burden
imposed
by
the
two
units
in
the
relay
is
shown
in
Table
IV
.
*
TABLE
IV
VOLTS
HERTZ
R
X
PF
WATTS
VA
120
60
386
536
0.59
12.74
21.8
120
50
497
-
523
0.69
13.74
20.0
The
potential
burden
is
maximum
when
the
restraint
taps
,
TR
,
are
set
for
100
and
the
angle
of
maximum
torque
is
near
25
degrees
lead
.
At
any
tap
setting
,
TR
,
the
potential
burden
for
each
unit
will
be
as
follows
:
Watts
+
jVars
=
(
A
+
jB
)
x
*
Indicates
Revision
8
Courtesy of NationalSwitchgear.com
GEK
-
49778
where
:
A
=
watts
,
when
TR
=
100
B
=
vars
,
when
TR
=
100
See
Table
V
for
values
of
A
and
B
.
TABLE
V
MAXIMUM
TORQUE
ANGLE
(
LEAD
)
JUMPERS
13
-
14
AND
15
-
16
WATTS
WATTS
(
A
)(
B
)
VOLTS
HERTZ
120
5
°
60
ON
-
2.70
-
3.50
-
6.50
5.20
120
10
°
60
ON
5.70
120
60
25
°
ON
6.30
120
60
300
OFF
8.20
6.20
120
60
350
OFF
6.40
7.55
120
50
50
ON
5.15
-
2.30
-
3.33
-
7.20
10
O
120
50
5.90
ON
120
50
25
°
ON
6.95
120
50
30
°
OFF
6.60
4.83
120
50
35
°
OFF
6.30
4.00
The
total
potential
burden
will
be
the
sum
of
the
burden
from
each
unit
.
Normally
both
units
will
be
set
for
the
same
reach
and
maximum
torque
angle
,
so
it
will
only
be
necessary
to
calculate
the
burden
for
one
unit
.
This
value
will
be
the
burden
on
each
of
the
two
potential
devices
.
The
burden
measured
on
any
unit
may
vary
plus
or
minus
ten
percent
from
the
instruction
book
values
,
due
to
allowable
tolerances
on
capacitors
and
coils
.
CALCULATION
OF
SETTINGS
The
exact
settings
to
be
made
on
the
ohm
units
in
Type
CEX
57
relays
will
depend
on
the
particular
application
.
When
used
in
blinder
applications
,
the
primary
objective
is
to
restrict
the
tripping
area
of
the
tripping
units
to
avoid
operation
on
load
impedance
.
Thus
,
the
reach
setting
should
be
made
so
that
operation
is
prevented
during
maximum
load
flow
or
stable
power
swing
conditions
.
The
angle
setting
should
be
made
so
that
the
ohm
units
will
plot
parallel
to
the
protected
line
.
When
out
-
of
-
step
tripping
during
power
swings
is
required
,
tripping
during
stable
swings
can
be
prevented
,
and
the
breaker
duty
minimized
,
by
permitting
tripping
only
after
a
favorable
angle
is
reached
.
Thus
,
the
reach
settings
to
be
made
will
be
Indicates
Revision
9
Courtesy of NationalSwitchgear.com
GEK
-
49778
Specific
details
for
dependent
on
particular
system
conditions
and
configuration
.
determining
the
settings
for
transmission
line
or
generator
applications
can
be
found
in
the
appropriate
instruction
book
for
Type
NAA
or
GSY
relays
,
ac
mentioned
earlier
.
Once
the
desired
reach
and
angle
has
been
determined
,
it
is
only
necessary
to
calculate
and
set
the
restraint
taps
to
meet
the
desired
reach
.
The
restraint
tap
setting
can
be
calculated
as
follows
:
T
=
(
Ml
(
TB
)
ZM
T
=
restraint
tap
setting
in
percent
Tg
=
basic
reach
tap
ZM
=
desired
reach
in
secondary
ohms
at
the
selected
torque
angle
For
example
,
refer
to
Figure
3
and
4
and
assume
ZM
should
be
set
to
reach
five
ohms
at
the
torque
angle
shown
.
Base
reach
taps
of
0.5
,
1.5
and
3.0
ohms
are
available
.
Always
select
the
highest
base
reach
tap
that
will
provide
the
desired
reach
setting
.
For
this
example
,
use
the
3.0
ohm
tap
.
Therefore
,
where
:
T
=
(
100
)
(
3.0
)
=
60
percent
5
Set
the
restraint
taps
for
both
ohm
units
to
60
percent
.
CONSTRUCTION
The
Type
CEX
57
relays
are
assembled
in
a
medium
size
,
double
end
(
M
2
)
drawout
case
,
having
studs
at
both
ends
in
the
rear
for
external
connections
.
The
electrical
connections
between
the
relay
units
and
the
case
studs
are
made
through
stationary
molded
inner
and
outer
blocks
,
between
which
nests
a
removable
connection
plug
,
which
completes
the
circuit
.
The
outer
blocks
attached
to
the
case
have
studs
for
the
external
connections
,
and
the
inner
blocks
have
terminals
for
the
internal
connections
.
Every
circuit
in
the
drawout
case
has
an
auxiliary
brush
,
as
shown
in
Figure
8
,
to
provide
adequate
overlap
when
the
connecting
plug
is
withdrawn
or
inserted
.
Some
circuits
are
equipped
with
shorting
bars
(
see
internal
connections
)
and
on
those
circuits
,
it
is
especially
important
that
the
auxiliary
brush
make
contact
as
indicated
in
Figure
8
with
adequate
pressure
to
prevent
the
opening
of
important
interlocking
circuits
.
The
relay
mechanism
is
mounted
in
a
steel
framework
called
the
cradle
and
is
a
complete
unit
with
all
leads
terminated
at
the
inner
block
.
This
cradle
is
held
firmly
in
the
case
with
a
latch
at
both
top
and
bottom
and
by
a
guide
pin
at
the
back
of
the
case
.
The
connecting
plug
,
besides
making
the
electrical
connections
between
the
respective
blocks
of
the
cradle
and
case
,
also
locks
the
latch
in
place
.
The
cover
,
which
is
drawn
to
the
case
by
thumbscrews
,
holds
the
connecting
plugs
in
place
.
The
target
reset
mechanism
is
a
part
of
the
cover
assembly
.
10
Courtesy of NationalSwitchgear.com
GEK
-
49778
The
relay
case
is
suitable
for
either
a
semi
-
flush
or
surface
mounting
on
all
panels
up
to
two
inches
thick
and
appropriate
hardware
is
available
.
However
,
panel
thickness
must
be
indicated
on
the
relay
order
to
insure
that
proper
hardware
will
be
included
.
A
separate
testing
plug
can
be
inserted
in
place
of
the
connecting
plug
to
test
the
relay
in
place
on
the
panel
either
from
its
own
source
of
current
and
voltage
,
or
from
other
sources
.
Or
,
the
relay
can
be
drawn
out
and
replaced
by
another
relay
which
has
already
been
tested
in
the
laboratory
.
Figure
1
shows
the
relay
removed
from
its
case
with
all
major
components
identified
.
Symbols
used
to
identify
circuit
components
are
the
same
as
those
which
appear
on
the
internal
connection
diagrams
in
Figures
9
,
10
and
11
.
The
relays
include
two
angle
-
impedance
units
mounted
on
the
front
of
the
cradle
and
a
tapped
autotransformer
.
The
Type
CEX
57
F
also
has
an
auxiliary
unit
(
telephone
-
type
)
mounted
at
the
top
.
The
angle
-
impedance
unit
assembly
includes
the
four
pole
unit
,
two
potentiometers
,
one
capacitor
and
two
tap
blocks
for
setting
basic
reach
.
The
upper
potentiometer
(
PI
for
the
top
unit
or
P
2
for
the
lower
unit
)
is
used
to
set
the
angle
of
maximum
torque
.
The
lower
potentiometer
(
P
3
for
the
top
unit
or
P
4
for
the
lower
unit
)
is
used
to
set
basic
reach
to
tap
value
.
The
operating
coil
consists
of
two
current
coils
,
and
both
coils
have
three
taps
.
These
taps
come
to
the
two
tap
blocks
mounted
on
the
left
side
of
the
unit
.
These
taps
determine
the
basic
reach
of
the
unit
,
and
both
tap
plugs
are
normally
set
for
the
same
tap
value
.
See
Table
II
for
data
on
how
the
basic
reach
ohms
vary
as
the
angle
of
maximum
torque
is
changed
.
RECEIVING
,
HANDLING
AND
STORAGE
These
relays
,
when
not
included
as
part
of
a
control
panel
will
be
shipped
in
cartons
designed
to
protect
them
against
damage
.
Immediately
upon
receipt
of
a
relay
,
examine
it
for
any
damage
sustained
in
transit
.
If
damage
resulting
from
rough
handling
is
evident
,
file
a
damage
claim
at
once
with
the
transportation
company
and
promptly
notify
the
nearest
General
Electric
Apparatus
Sales
Office
.
Reasonable
care
should
be
exercised
in
unpacking
the
relay
in
order
that
none
of
the
parts
are
damaged
or
the
adjustments
disturbed
.
If
the
relays
are
not
to
be
installed
immediately
,
they
should
be
stored
in
their
original
cartons
in
a
place
that
is
free
from
moisture
,
dust
and
metallic
chips
.
Foreign
matter
collected
on
the
outside
of
the
case
may
find
its
way
inside
when
the
cover
is
removed
,
and
cause
trouble
in
the
operation
of
the
relay
.
11
Courtesy of NationalSwitchgear.com
GEK
-
49778
ACCEPTANCE
TESTS
Immediately
upon
receipt
of
the
relay
,
an
inspection
and
acceptance
test
should
be
made
to
insure
that
no
damage
has
been
sustained
in
shipment
,
and
that
the
relay
calibrations
have
not
been
disturbed
,
readjustment
is
necessary
,
refer
to
SERVICING
.
If
examination
or
test
indicates
that
VISUAL
INSPECTION
Check
the
nameplate
stamping
to
insure
that
the
model
number
and
rating
of
the
relay
agree
with
the
requisition
.
Remove
the
relay
from
its
case
and
check
that
there
are
no
broken
or
cracked
molded
parts
or
other
signs
of
physical
damage
,
and
that
all
screws
are
tight
.
MECHANICAL
INSPECTION
There
should
be
no
noticeable
friction
in
the
rotating
structure
of
the
units
.
Make
sure
the
control
springs
are
not
deformed
,
and
that
spring
convolutions
do
not
touch
each
other
.
1
.
2
.
With
the
relay
well
-
leveled
in
its
upright
position
,
the
left
contacts
of
both
units
must
be
open
.
The
moving
contacts
of
the
units
should
rest
against
the
right
contact
.
Check
the
location
of
the
contact
brushes
on
the
cradle
and
case
blocks
against
the
internal
connection
diagram
for
the
relay
.
The
rotating
shaft
end
play
should
be
0.005
inch
to
0.010
inch
.
The
contact
gap
should
be
0.018
inch
to
0.020
inch
.
The
contact
wipe
should
be
0.003
inch
to
0.006
inch
.
3
.
4
.
5
.
6
.
7
.
ELECTRICAL
CHECKS
-
OHM
UNIT
All
tests
should
be
made
with
the
relay
in
its
case
.
Before
any
electrical
checks
are
made
on
the
units
,
the
relay
should
be
connected
as
shown
in
Figure
12
B
,
and
allowed
to
warm
up
for
approximately
15
minutes
with
the
potential
circuit
alone
energized
at
rated
voltage
,
and
the
restraint
taps
set
at
100
percent
.
The
units
were
warmed
up
prior
to
factory
adjustment
,
and
if
they
are
rechecked
when
cold
,
they
will
have
a
tendency
to
underreach
by
three
or
four
percent
.
Accurately
calibrated
meters
are
,
of
course
,
essential
.
Check
the
factory
setting
and
calibration
by
means
of
the
tests
described
in
the
following
sections
.
The
units
were
carefully
adjusted
at
the
factory
,
and
these
settings
should
not
be
disturbed
unless
the
following
checks
indicate
conclusively
that
the
settings
have
been
disturbed
.
If
readjustments
are
necessary
,
refer
to
the
section
on
SERVICING
for
recommended
procedures
.
12
Courtesy of NationalSwitchgear.com
GEK
-
49778
Test
connections
for
checking
correct
unit
operation
.
Jumper
studs
13
to
14
and
15
to
16
.
Control
Spring
Adjustment
:
Be
sure
that
the
relay
is
level
in
its
upright
position
.
Leave
the
relay
connected
as
shown
in
Figure
12
B
,
and
leave
the
restraint
taps
in
the
100
percent
position
.
Put
the
basic
reach
taps
in
the
1.5
ohm
taps
.
With
the
voltage
set
for
zero
,
the
current
required
to
close
the
left
contact
should
be
as
shown
below
:
CEX
57
D
CEX
57
E
CEX
57
F
Amperes
to
Close
Left
Contact
1.2
-
1.5
0.85
-
1.00
1.2
-
1.5
Clutch
Adjustment
:
Remove
jumpers
from
studs
13
-
14
and
15
-
16
.
With
the
connections
shown
in
Figure
12
B
,
set
the
phase
angle
to
185
degrees
(
I
leads
V
)
for
the
top
unit
,
or
5
degrees
(
I
leads
V
)
for
the
lower
unit
.
Put
restraint
taps
in
100
percent
,
basic
reach
taps
in
the
3.0
ohm
taps
,
and
set
for
rated
voltage
.
Increase
the
current
until
the
clutch
just
slips
.
The
current
should
be
between
22
and
30
amps
.
The
clutch
slip
can
be
detected
by
observing
the
nut
at
the
top
of
the
rotating
shaft
assembly
.
This
nut
will
turn
when
the
clutch
slips
,
but
the
moving
contact
will
remain
in
contact
with
the
left
stationary
contact
.
Ohmic
Reach
Connect
the
relay
per
Figure
12
B
.
Set
the
phase
angle
to
maximum
torque
(
I
leads
V
by
five
degrees
if
factory
adjusted
)
.
With
restraint
taps
on
100
percent
,
basic
reach
taps
on
1.5
ohms
,
and
V
=
30
volts
,
determine
current
to
just
close
the
left
contact
of
the
upper
unit
.
The
current
should
be
between
9.7
and
10.3
amperes
.
f
or
the
lower
unit
,
repeat
as
above
,
except
set
the
phase
angle
to
185
degrees
(
I
leads
V
)
.
Note
that
the
mho
units
see
a
phase
-
to
-
phase
fault
of
twice
the
basic
minimum
reach
for
the
test
conditions
.
Angle
of
Maximum
Torque
:
To
check
the
angle
of
maximum
torque
,
again
use
the
connections
of
Figure
12
B
.
Set
the
phase
shifter
to
maximum
torque
angle
,
plus
30
degrees
.
The
current
to
close
the
left
contact
should
be
82
to
91
percent
of
the
value
determined
in
"
Ohmic
Reach
"
above
.
Repeat
the
above
check
with
the
phase
angle
set
for
maximum
torque
angle
,
minus
30
degrees
.
The
current
to
close
the
left
contact
should
also
be
82
to
91
percent
of
the
value
determined
in
"
Ohmic
Reach
.
"
ELECTRICAL
CHECKS
-
AUXILIARY
UNIT
(
CEX
57
F
ONLY
)
Select
the
proper
tap
for
the
DC
voltage
to
be
used
on
the
relay
.
13
Courtesy of NationalSwitchgear.com
GEK
-
49778
Apply
75
percent
of
rated
DC
voltage
to
studs
1
and
11
,
with
plus
DC
on
stud
11
.
Close
the
left
contact
of
both
induction
cylinder
units
.
The
auxiliary
relay
should
pick
up
.
INSTALLATION
PROCEDURE
LOCATION
The
relay
should
be
installed
in
a
location
that
is
clean
,
dry
,
free
from
dust
,
and
well
lighted
to
facilitate
inspection
and
testing
.
MOUNTING
The
relay
should
be
mounted
on
a
vertical
surface
.
The
outline
and
panel
drilling
dimensions
are
shown
in
Figure
14
.
CONNECTIONS
The
internal
connections
diagrams
for
the
relays
are
shown
in
Figures
9
,
10
and
An
elementary
diagram
of
typical
external
connections
is
shown
in
Figure
5
.
VISUAL
INSPECTION
11
.
Remove
the
relay
from
its
case
and
check
that
there
are
no
broken
or
cracked
component
parts
,
and
that
all
screws
are
tight
.
MECHANICAL
INSPECTION
Recheck
the
seven
adjustments
detailed
in
the
MECHANICAL
INSPECTION
section
of
ACCEPTANCE
TESTS
.
INSPECTION
Before
placing
a
relay
into
service
,
the
following
mechanical
adjustments
should
be
checked
:
ANGLE
-
IMPEDANCE
UNIT
There
should
be
no
noticeble
friction
in
the
rotating
structure
of
the
unit
.
The
unit
'
s
moving
contacts
should
just
return
to
the
right
contact
when
the
relay
is
de
-
energized
and
in
the
vertical
position
.
There
should
be
approximately
0.005
to
0.010
inch
end
play
in
the
shaft
of
the
rotating
structure
.
The
lower
jewel
screw
bearing
should
be
screwed
firmly
into
place
,
and
the
top
pivot
locked
in
place
by
its
set
screw
.
If
the
jewel
should
become
cracked
or
dirty
,
the
screw
assembly
can
be
removed
from
the
bottom
of
the
unit
and
examined
.
When
replacing
a
jewel
,
have
the
top
pivot
engaged
in
the
shaft
while
screwing
in
the
jewel
screw
.
14
Courtesy of NationalSwitchgear.com
GEK
-
49778
All
nuts
and
screws
should
be
tight
,
particularly
on
the
tap
plugs
.
The
felt
gasket
on
the
cover
should
be
securely
cemented
in
place
in
order
to
keep
out
dust
.
Determine
the
impedance
and
phase
angle
seen
by
the
relays
.
Once
the
impedance
and
phase
angle
is
determined
,
the
tap
value
at
which
the
relay
will
just
operate
can
be
calculated
.
It
is
then
only
necessary
to
reduce
the
tap
setting
of
the
relay
until
the
units
operate
,
and
see
how
close
the
actual
tap
value
found
checks
with
the
calculated
value
.
The
calculated
value
should
take
into
account
the
shorter
reach
of
the
unit
at
low
currents
.
This
effect
is
shown
in
Figure
14
.
A
procedure
to
check
most
of
the
possible
open
circuits
in
the
AC
portion
of
the
relay
is
as
follows
:
(
a
)
Open
the
potential
circuit
by
removing
one
of
the
#
1
and
one
of
the
#
2
tap
plugs
.
Place
current
taps
in
the
1.5
ohm
taps
.
With
current
greater
than
two
amps
flowing
in
the
current
coils
,
the
left
contact
of
the
unit
should
close
.
(
b
)
(
c
)
Replace
the
#
1
and
#
2
restraint
tap
plugs
.
With
120
volts
on
the
relay
,
one
unit
should
close
its
right
contact
,
while
the
other
unit
should
have
increased
torque
closing
the
left
contact
.
Which
unit
has
its
left
contact
closed
,
and
which
has
its
right
closed
,
is
determined
by
the
direction
of
the
current
in
the
current
circuit
,
relative
to
the
voltage
on
the
potential
circuit
.
PERIODIC
CHECKS
AND
ROUTINE
MAINTENANCE
In
view
of
the
vital
role
of
protective
relays
in
the
operation
of
a
power
system
,
The
interval
between
it
is
important
that
a
periodic
test
program
be
followed
,
periodic
checks
will
vary
depending
upon
environment
,
type
of
relay
and
the
user
'
s
experience
with
periodic
testing
.
Until
the
user
has
accumulated
enough
experience
to
select
the
test
interval
best
suited
to
his
individual
requirements
,
it
is
suggested
that
the
points
listed
under
ACCEPTANCE
TESTS
be
checked
at
an
interval
of
from
one
to
two
years
.
CONTACT
CLEANING
A
flexible
burnishing
tool
should
be
used
for
cleaning
relay
contacts
.
This
is
a
flexible
strip
of
metal
with
an
etched
-
roughened
surface
,
which
in
effect
resembles
a
superfine
file
.
The
polishing
action
of
this
file
is
so
delicate
that
no
scratches
are
left
on
the
contacts
,
yet
it
cleans
off
any
corrosion
thoroughly
and
rapidly
,
flexibility
of
the
tool
insures
the
cleaning
of
the
actual
points
of
contact
.
Relay
contacts
should
never
be
cleaned
with
knives
,
files
,
or
abrasive
paper
or
cloth
.
The
15
Courtesy of NationalSwitchgear.com
GEK
-
49778
SERVICING
If
the
unit
calibrations
are
found
to
be
out
of
limits
during
installation
or
periodic
tests
,
they
should
be
recalibrated
as
outlined
in
the
following
paragraphs
.
The
calibrations
should
be
made
in
the
laboratory
.
The
circuit
components
listed
below
,
normally
considered
as
factory
adjustments
,
are
used
in
recalibrating
the
units
.
The
parts
may
be
physically
located
on
Figures
1
and
2
.
Their
location
in
the
relay
circuit
is
shown
on
the
internal
connection
diagrams
,
Figures
10
,
11
and
12
.
PI
:
Angle
of
maximum
torque
adjustment
on
upper
unit
P
2
:
Angle
of
maximum
torque
adjustment
on
lower
unit
P
3
Ohmic
reach
of
top
unit
P
4
:
Ohmic
reach
of
bottom
unit
Before
making
pickup
or
phase
angle
adjustments
on
the
units
,
they
should
be
allowed
to
heat
up
for
approximately
15
minutes
,
energized
with
rated
voltage
alone
,
and
the
restraint
tap
leads
set
for
100
percent
.
It
is
also
important
that
the
relay
is
mounted
in
an
upright
position
so
that
the
units
are
level
.
NOTE
:
CONTROL
SPRING
ADTUSTMENT
Make
connections
to
the
relay
as
shown
in
Figure
12
B
:
Set
voltage
to
zero
volts
Put
basic
reach
taps
in
1.5
ohm
taps
Set
current
to
1.0
ampere
.
Insert
the
blade
of
a
thin
screwdriver
into
one
of
the
slots
in
the
edge
of
the
spring
adjusting
ring
(
see
Figure
2
)
and
turn
the
ring
until
the
left
contact
of
the
unit
just
closes
.
Turning
the
ring
to
the
right
will
increase
the
current
required
to
close
the
left
contact
.
When
the
left
contact
just
closes
at
1.0
ampere
,
reduce
the
current
to
zero
,
and
check
that
the
right
contact
is
closed
.
ANGLE
OF
MAXIMUM
TORQUE
ADTUSTMENT
The
angle
of
maximum
torque
is
primarily
controlled
by
the
adjustment
of
the
upper
rheostat
on
each
unit
(
PI
for
the
upper
unit
,
or
P
2
for
the
lower
unit
)
,
and
by
whether
a
jumper
is
applied
across
studs
13
-
14
and
15
-
16
.
The
lower
rheostat
on
each
unit
(
P
3
for
the
upper
unit
,
or
P
4
for
the
lower
unit
)
,
has
a
secondary
effect
on
the
angle
of
maximum
torque
.
For
angle
of
maximum
torque
between
5
and
25
degrees
,
a
jumper
should
be
connected
between
studs
13
-
14
,
and
a
second
jumper
between
studs
15
-
16
.
For
angle
of
maximum
torque
between
30
and
35
degrees
,
no
connections
should
be
made
to
studs
13
,
14
,
15
or
16
.
For
angle
of
maximum
torque
between
25
and
30
degrees
,
determine
whether
the
jumpers
between
studs
13
-
14
and
studs
15
-
16
should
or
should
not
be
used
.
This
will
vary
from
unit
to
unit
,
depending
upon
actual
value
of
capacitors
Cl
and
C
2
.
16
Courtesy of NationalSwitchgear.com
GEK
-
49778
The
relays
are
shipped
from
the
factory
with
the
maximum
torque
angle
set
for
five
degrees
(
I
leads
V
)
.
For
a
different
angle
of
maximum
torque
,
proceed
as
follows
:
Connect
the
relay
as
shown
in
Figure
12
B
.
Jumper
studs
13
-
14
and
studs
15
-
16
if
required
.
Put
basic
reach
taps
in
1.5
ohm
tap
.
With
restraint
taps
set
for
100
percent
,
apply
60
volts
to
relay
.
Set
current
to
15
amperes
.
Turn
the
phase
shifter
and
determine
the
two
angles
at
which
the
left
contact
just
closes
(
angle
of
zero
torque
)
.
Find
the
angle
of
maximum
torque
as
follows
:
Add
the
two
angles
found
above
Divide
the
sum
by
two
.
This
will
be
the
angle
of
maximum
torque
for
the
lower
unit
.
For
the
upper
unit
,
subtract
180
degrees
from
the
value
to
get
the
maximum
torque
angle
.
For
example
:
Assume
the
top
unit
closes
its
left
contact
at
52
degrees
and
326
degrees
.
Adding
the
two
values
52
+
326
=
378
degrees
.
Dividing
by
two
equals
189
degrees
;
subtracting
180
degrees
equals
nine
degrees
for
the
angle
of
maximum
torque
.
If
studs
13
-
14
and
studs
15
-
16
are
jumpered
,
the
upper
rheostat
on
the
unit
should
be
turned
clockwise
to
make
the
angle
of
maximum
torque
lower
;
or
counterclockwise
to
make
the
angle
of
maximum
torque
higher
.
If
studs
13
-
14
and
studs
15
-
16
are
not
jumpered
,
the
upper
rheostat
on
the
unit
should
be
turned
counterclockwise
to
make
the
angle
of
maximum
torque
lower
,
and
clockwise
'
to
make
the
angle
of
maximum
torque
higher
.
If
the
upper
rheostat
is
turned
completely
counterclockwise
,
the
rheostat
will
be
at
zero
ohms
,
and
the
angle
of
maximum
torque
will
be
approximately
the
same
whether
studs
13
-
14
and
studs
15
-
16
are
shorted
or
left
unshorted
.
This
is
the
angle
that
determines
whether
to
short
studs
13
-
14
and
studs
15
-
16
.
For
angles
of
maximum
torque
below
this
value
,
studs
13
-
14
and
studs
15
-
16
must
be
jumpered
.
For
angles
of
maximum
torque
above
this
value
,
studs
13
-
14
and
studs
15
-
16
should
not
be
shorted
.
This
value
will
be
between
26
and
30
degrees
.
1
.
2
.
3
.
4
.
5
.
6
.
a
)
b
)
7
.
8
.
9
.
BASIC
REACH
OHMS
When
the
angle
of
maximum
torque
is
set
for
the
desired
value
by
the
tests
outlined
in
ANGLE
OF
MAXIMUM
TORQUE
ADJUSTMENT
,
the
basic
reach
should
be
checked
as
follows
:
Turn
the
phase
shifter
to
set
test
circuit
to
angle
of
maximum
torque
.
1
.
17
Courtesy of NationalSwitchgear.com
GEK
-
49778
Set
the
voltage
to
the
values
given
in
Table
VI
,
and
determine
the
current
to
just
cause
the
left
contact
to
close
.
This
value
should
be
as
shown
in
Table
VI
.
2
.
CORE
ADJUSTMENT
(
IF
REQUIRED
)
The
core
adjustment
is
made
as
follows
:
Adjust
the
control
spring
until
the
moving
contact
is
not
touching
either
the
right
or
left
contact
when
the
relay
is
de
-
energized
.
Apply
rated
voltage
to
studs
3
-
4
for
15
minutes
to
allow
the
potential
circuit
to
heat
up
.
Adjust
the
core
until
the
moving
contact
remains
in
the
same
position
with
studs
3
-
4
energized
at
rated
voltage
,
or
with
studs
3
-
4
de
-
energized
.
1
.
2
.
3
.
TABLE
VI
PHASE
ANGLE
SETTING
ANGLE
OF
MAX
.
TORQUE
BOTTOM
BASIC
TOP
VOLTAGE
ON
STUDS
3
-
4
CURRENT
PICKUP
UNIT
UNIT
OHMS
5
°
185
1.43
-
1.58
1.22
-
1.40
1.14
-
1.26
1.02
-
1.13
0.95
-
1.07
0.92
-
1.11
1.05
-
1.20
5
12.7
-
14.0
14.3
-
16.4
15.9
-
17.6
17.7
-
19.6
18.7
-
21.0
18.0
-
21.7
16.7
-
19.1
40
10
°
10
190
40
150
15
195
40
20
°
20
200
40
25
°
25
205
40
300
30
210
40
350
35
215
40
There
should
be
no
current
in
the
current
circuits
(
studs
5
-
6
and
studs
7
-
8
)
when
the
core
adjustment
test
is
being
made
.
When
the
core
adjustment
test
is
completed
,
reset
the
control
spring
per
the
paragraph
on
CONTROL
SPRING
ADJUSTMENT
.
RENEWAL
PARTS
Sufficient
quantities
of
renewal
parts
should
be
kept
in
stock
for
the
prompt
replacement
of
any
that
are
worn
,
broken
or
damaged
.
When
ordering
renewal
parts
,
address
the
nearest
Sales
Office
of
the
General
Electric
Company
.
Specify
the
name
of
the
part
wanted
,
quantity
required
,
and
complete
nameplate
data
,
including
the
serial
number
,
of
the
relay
.
indicates
Revision
18
Courtesy of NationalSwitchgear.com
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