GE CEY53A User manual
GEK
-
7351
CONTENTS
PAGE
DESCRIPTION
APPLICATION
CALCULATION
OF
SETTINGS
RATINGS
5
5
5
6
CONTACTS
CONSTRUCTION
OPERATING
PRINCIPLES
MHO
UNIT
CHARACTERISTICS
IMPEDANCE
CHARACTERISTICS
DIRECTIONAL
ACTION
UNDERREACH
MEMORY
ACTION
TRANSIENT
OVERREACH
OPERATING
TIME
VERNIER
ADJUSTMENT
FOR
LOW
TAP
SETTINGS
6
7
.
7
7
8
8
8
8
9
9
9
9
BURDENS
9
9
CURRENT
CIRCUITS
POTENTIAL
CIRCUITS
MECHANICAL
ADJUSTMENTS
SERVICING
TESTING
WITH
THE
X
+
R
EQUIPMENT
PORTABLE
TEST
EQUIPMENT
ELECTRICAL
TESTS
DRAWOUT
RELAYS
GENERAL
POWER
REQUIREMENTS
GENERAL
RECEIVING
,
HANDLING
AND
STORAGE
PERIODIC
CHECKS
AND
ROUTINE
MAINTENANCE
CONTACT
CLEANING
RENEWAL
PARTS
INSTALLATION
PROCEDURE
LOCATION
MOUNTING
VISUAL
INSPECTION
MECHANICAL
INSPECTION
10
10
10
12
12
12
12
12
13
13
13
13
13
13
13
14
14
3
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GEK
-
7351
MHO
DISTANCE
RELAY
FOR
SHUNT
REACTOR
PROTECTION
TYPE
CEY
53
A
DESCRIPTION
The
type
CEY
53
A
relay
is
a
single
phase
zone
one
mho
distance
relay
specifically
designed
for
shunt
reactor
protection
.
It
provides
instantaneous
protection
against
turn
-
to
-
turn
and
single
phase
-
to
-
ground
faults
.
The
relay
is
mounted
in
a
double
unit
single
ended
size
Ml
drawout
case
and
is
provided
with
a
target
seal
-
in
unit
.
Three
relays
are
required
,
one
per
phase
,
for
each
shunt
reactor
installation
.
APPLICATION
The
type
CEY
53
A
relay
is
a
zone
one
mho
distance
relay
specifically
designed
for
shunt
reactor
protection
.
The
external
connections
are
shown
in
Figure
3
.
This
application
shows
the
reactors
connected
as
an
integral
part
of
the
transmission
line
with
the
relays
supplied
with
line
side
potential
.
When
a
transmission
line
having
integral
shunt
reactors
is
first
deenergized
,
there
will
be
a
trapped
voltage
remaining
on
the
line
which
will
be
oscillating
at
some
matural
frequency
as
determined
by
the
total
reactance
and
the
line
distributed
shunt
capacitance
.
The
oscillation
frequency
varies
from
about
40
to
70
Hz
for
minimum
to
maximum
reactor
compensation
respectively
.
Since
the
relay
would
normally
receive
its
potential
from
line
side
coupling
capacitor
potential
devices
,
it
would
be
subjected
to
these
voltage
oscillations
.
If
the
relay
were
to
develop
operating
torque
and
close
its
contacts
under
these
conditions
,
it
would
most
likely
prevent
the
successful
high
speed
reclosing
of
the
line
.
The
relay
design
is
such
that
its
ohmic
reach
is
appreciably
shortened
at
frequencies
lower
than
rated
frequency
.
The
curve
of
Figure
4
shows
the
mho
unit
response
over
a
range
of
38
to
70
Hz
.
As
the
frequency
is
decreased
the
mho
unit
maximum
torque
angle
becomes
less
lagging
and
also
the
diameter
of
the
mho
circle
decreases
.
These
variations
are
shown
in
the
curves
of
Figure
5
.
The
curve
of
Figure
4
is
a
composite
showing
the
effect
of
both
of
the
variations
shown
in
the
curves
of
Figure
5
with
an
85
degree
angle
line
as
reference
.
Shunt
reactors
designed
to
be
connected
to
transmission
lines
will
generally
begin
to
saturate
at
just
over
rated
voltage
.
The
apparent
reduction
of
reactance
at
elevated
voltages
must
be
considered
in
setting
the
relay
so
as
to
avoid
misoperation
of
the
reactor
protection
on
the
line
overvoltage
conditions
expected
.
When
the
transmission
line
section
and
its
connected
reactor
are
energized
at
the
zero
point
in
the
voltage
wave
,
the
reactor
inrush
current
produced
will
have
maximum
offset
and
will
saturate
the
reactor
to
some
degree
.
Thus
the
apparent
reactance
will
be
reduced
.
The
relay
setting
must
not
be
so
sensitive
as
to
respond
to
this
reduced
apparent
reactance
otherwise
line
retripping
would
result
.
The
sensitivity
of
the
protection
for
the
reactor
will
depend
upon
the
relay
setting
and
the
reactor
design
.
The
relay
sensitivity
will
first
be
limited
by
the
considerations
previously
discussed
so
that
it
will
not
trip
incorrectly
on
energizing
or
overvoltage
,
etc
.
The
resulting
setting
will
determine
the
degree
of
protection
remaining
.
However
,
as
one
example
of
turn
-
to
-
turn
protection
,
calculations
of
a
particular
reactor
design
indicated
that
a
short
circuit
involving
only
5
percent
of
the
total
turns
would
reduce
the
apparent
impedance
of
the
reactor
to
approximately
25
percent
of
its
rated
value
.
Thus
,
fairly
good
protection
coverage
is
provided
.
When
the
reactor
is
part
of
the
transmission
line
,
clearing
of
any
reactor
faults
requires
the
tripping
of
a
remote
line
breaker
.
The
external
connections
of
Figure
1
show
a
21
/
X
external
auxiliary
device
operated
by
the
CEY
53
A
trip
circuit
to
provide
transfer
trip
keying
to
accomplish
this
function
.
CALCULATION
OF
SETTINGS
For
the
purpose
of
illustrating
relay
settings
assume
a
shunt
reactor
of
100
MVAR
per
phase
on
a
500
KV
system
.
The
reactor
rated
reactance
is
therefore
:
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
.
further
:
i
n
forma
tion
be
desired
or
should
particular
problems
arise
which
are
not
covered
sufficiently
for
the
purchaser
'
s
purposes
,
the
matter
should
be
referred
to
the
General
Electric
Company
.
Should
Tc
the
extent
required
the
products
described
herein
meet
applicable
ANSI
,
IEEE
and
NEMA
standards
;
but
no
such
assurance
is
given
with
respect
to
local
codes
and
ordinances
because
they
vary
greatly
.
5
Courtesy of NationalSwitchgear.com
GEK
-
7351
X
=
(
ELN
)
2
=
(
289
)
2
X
106
=
100
X
106
835
ohms
primary
VAR
CT
Ratio
PY
Ratio
Xsec
=
Xpri
Assume
CT
Ratio
=
600
/
5
PT
Ratio
-
289
,
000
/
120
(
1
ine
-
to
-
neutral
)
Xsec
=
41.6
ohms
(
1
per
unit
)
Assume
maximum
short
time
overvoltage
are
1.3
per
unit
.
From
the
reactor
saturation
curve
determine
the
current
level
at
this
voltage
.
Assume
1.53
per
unit
current
1.30
X
at
1.3
pu
voltage
=
=
0
,
85
pu
-
35.4
ohms
1753
The
reactor
apparent
impedance
under
extreme
inrush
conditions
when
energizing
as
discussed
under
APPLICATION
will
have
to
be
calculated
or
determined
by
test
.
When
this
value
is
known
,
compare
it
with
the
apparent
reactance
determined
under
overvoltage
conditions
as
shown
above
.
Using
the
smaller
of
the
two
reactances
,
reduce
this
value
by
a
suitable
margin
of
perhaps
10
to
15
percent
to
determine
the
required
relay
reach
setting
.
Assume
the
relay
to
be
set
for
0.55
pu
or
22.9
ohms
secondary
.
For
best
performance
select
the
highest
possible
relay
basic
minimum
tap
TB
available
that
can
be
used
for
the
required
setting
.
For
this
case
,
connect
the
two
relay
current
coils
in
series
as
is
shown
in
the
external
connections
of
Figure
3
.
The
relay
basic
minimum
taps
will
now
be
twice
the
nameplate
value
.
For
example
if
the
nameplate
taps
are
0.75
/
1.5
/
3
,
connecting
the
two
current
coils
in
series
will
change
these
tap
values
to
1.5
/
3
/
6
.
In
this
case
select
the
6
ohm
tap
.
The
percent
restraint
tap
T
is
determined
by
the
following
rel
ation
j
_
100
TB
cos
(
9
-
0
)
Z
where
9
=
reactor
angle
,
assume
90
degrees
0
=
maximum
torque
angle
of
relay
,
75
degrees
.
Z
=
desired
reach
at
angle
9
=
100
(
6
)
cos
15
°
T
=
25
percent
22.9
RATINGS
The
type
CEY
53
A
relay
covered
by
these
instructions
is
available
for
120
volts
,
5
amperes
,
60
cycle
rating
.
The
1
second
rating
of
the
current
circuits
is
225
amperes
per
circuit
.
The
basic
minimum
reach
and
adjustment
ranges
of
the
mho
units
are
given
in
the
table
below
.
MHo
Unit
Basic
Min
.
*
Reach
0
N
ohms
Angie
of
Max
.
Tor
.
Range
0
-
N
ohms
75
°
Lag
750
Lag
0.75
/
1.5
/
3.0
1.5
/
3.0
/
6.0
Standard
Long
Reach
0.75
/
30
1.5
/
6
s
*
The
above
basic
minimum
reach
taps
are
for
only
one
current
coil
connected
in
the
current
circuit
or
for
'
both
current
coils
connected
in
parallel
.
If
the
two
current
coils
are
connected
in
series
these
basic
minimum
taps
are
multiplied
by
two
.
CONTACTS
The
contacts
of
the
CEY
53
relay
will
close
and
carry
momentarily
30
amperes
D
.
C
.
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
.
6
Courtesy of NationalSwitchgear.com
GEK
-
7351
Target
and
Seal
-
in
Unit
The
ratings
of
the
target
seal
-
in
unit
is
shown
below
.
2
Amp
Tap
0.2
Amp
1
ap
3
amps
0.3
amps
7
ohms
Carry
tripping
duty
Carry
continuously
D
.
C
.
resistance
Impedance
(
60
cycles
)
30
amps
3
amps
0.13
52
ohms
0.53
ohms
CONSTRUCTION
The
Type
CEY
53
relays
are
assembled
in
the
medium
size
single
ended
(
Ml
)
drawout
case
having
studs
at
one
end
in
the
rear
for
external
connections
.
The
electrical
connections
between
the
relay
and
case
studs
are
through
stationary
molded
inner
and
outer
blocks
between
which
nests
a
removable
connecting
plug
.
The
outer
blocks
have
the
terminals
for
the
internal
connections
.
Every
circuit
in
the
drawout
case
has
an
auxiliary
brush
,
as
shown
in
fig
.
6
,
to
provide
adequate
overlap
when
the
connecting
plug
is
withdrawn
or
inserted
.
Some
circuits
are
equipped
with
shorting
bars
(
see
internal
connections
in
Fig
.
7
,
and
on
those
circuits
,
it
is
especially
important
that
the
auxiliary
brush
make
contact
as
indicated
in
Fig
.
6
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
blocks
.
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
.
The
relay
case
is
suitable
for
either
semi
flush
or
surface
mounting
on
all
panels
up
to
2
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
.
Outline
and
panel
drilling
is
shown
in
Fig
.
8
.
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
which
has
been
tested
in
the
laboratory
.
Fig
.
i
shows
the
relay
removed
from
its
drawout
case
with
all
major
components
identified
.
Symbols
used
to
identify
circuit
components
are
the
same
as
those
which
appear
on
the
internal
connections
diagram
in
figure
7
,
All
adjustments
can
be
made
from
the
£
ront
of
the
relay
without
removing
the
relay
from
its
case
.
OPERATING
PRINCIPLES
he
mho
unit
of
the
CEY
53
A
relay
is
of
the
four
pole
induction
cylinder
construction
in
which
torque
produced
uy
the
interaction
between
a
polarizing
flux
and
fluxes
proportional
to
the
restraining
or
operating
quantities
.
The
method
of
obtaining
the
mho
characteristics
for
the
unit
is
described
below
.
MHO
UNIT
:
^
The
schematic
connections
of
the
Mho
unit
are
illustrated
in
fig
.
9
.
The
two
side
poles
,
energized
by
phase
-
to
-
neutral
voltage
,
produce
the
polarizing
flux
.
The
flux
from
the
front
and
rear
poles
,
energized
by
the
difference
between
the
secondary
voltage
of
the
transactor
TR
and
a
percentage
of
the
same
phase
-
to
-
neutral
voltage
,
interacts
with
the
polarizing
flux
to
produce
torque
.
The
torque
equation
can
be
written
as
follows
:
KE
(
IZT
-
TE
)
cos
f
Torque
(
i
)
where
:
phase
-
to
-
neutral
voltage
(
E
]
)
line
current
(
I
]
-
I
2
)
E
I
7
Courtesy of NationalSwitchgear.com
GEK
-
7351
Zj
=
transfer
impedance
of
transactor
Tp
K
=
the
inherent
design
contact
T
=
Out
-
transformer
tap
setting
B
=
Angle
between
E
and
(
IZj
-
E
)
.
That
this
equation
(
1
)
defines
a
mho
characteristic
can
be
shown
graphically
by
means
of
fig
.
10
.
The
vector
IZj
at
an
angle
0
determines
the
basic
minimum
reach
of
the
unit
for
a
particular
tap
setting
of
the
transactor
TR
primary
.
Assuming
finite
value
of
E
and
(
IZj
-
TE
)
,
the
balance
point
,
torque
=
0
,
will
occur
where
cos
B
=
0
,
that
is
where
the
angle
B
is
90
°
.
The
locus
of
the
terminus
of
vector
TE
(
point
A
in
fig
.
10
)
which
will
cause
the
angle
B
to
always
be
90
°
is
a
circle
passing
through
the
origin
and
with
the
vector
IZj
as
a
diameter
.
Considering
further
the
diagram
in
fig
.
10
,
we
note
that
the
angle
B
is
less
than
90
°
for
an
internal
fault
(
point
C
)
and
the
net
torque
will
be
in
the
closing
direction
(
cos
B
is
positive
)
;
and
that
the
angle
B
is
greater
than
90
°
for
an
external
fault
(
point
D
)
and
the
net
torque
will
be
in
the
opening
direction
(
cos
B
is
negative
)
.
CHARACTERISTICS
IMPEDANCE
CHARACTERISTICS
The
impedance
characteristics
of
the
mho
unit
is
shown
in
Fig
.
11
for
the
0.75
ohm
basic
minimum
reach
setting
at
a
maximum
torque
angle
of
75
°
.
This
circular
impedance
characteristic
can
be
enlarged
that
is
the
unit
reach
can
be
increased
up
to
10
/
1
by
reducing
the
percentage
of
the
terminal
voltage
supplied
to
the
taps
on
the
auto
transformer
.
The
circle
will
always
pass
through
the
origin
and
have
a
diameter
along
the
75
degree
impedance
line
equal
to
the
ohmic
reach
of
the
unit
as
expressed
by
the
following
equation
.
(
Input
Tap
)
Z
min
Unit
Tap
Setting
(
%
)
Ohmic
Reach
where
:
Input
Tap
=
100
%
Zmin
=
Basic
min
.
0
to
N
ohmic
reach
of
the
unit
(
tap
setting
)
Unit
Tap
=
Restraint
tap
lead
setting
on
transformer
taps
.
Setting
DIRECTIONAL
ACTION
The
mho
unit
is
adjusted
to
have
correct
directional
action
under
steady
state
conditions
.
For
faults
in
the
non
-
tripping
direction
,
the
contacts
will
remain
open
between
0
and
60
amperes
.
For
faults
in
the
tripping
direction
,
the
unit
will
close
its
contact
for
voltages
and
current
given
in
the
following
table
:
BASIC
MIN
.
REACH
TAP
0
-
N
VOLTAGE
STUDS
3
-
4
CURRENT
RANGE
STUDS
5
AND
8
JUMPER
6
AND
7
0.75
ohms
1.5
ohms
3.0
ohms
6.0
ohms
2.0
volts
2.0
volts
2.0
volts
2.0
volts
6
-
6 0
Amps
3
-
6 0
Amps
1.5
-
6 0
Amps
.
7 5
-
6 0
Amps
The
unit
is
tested
at
the
factory
in
the
1.5
ohm
tap
for
correct
directional
action
,
of
+
10
%
can
be
expected
in
the
other
taps
listed
above
.
A
variation
UNDERREACH
(
FIG
.
12
)
At
reduced
voltage
the
ohmic
value
at
which
the
unit
will
operate
may
be
somewhat
lower
than
the
calculated
value
.
This
pullback
or
reduction
unit
will
operate
for
all
points
to
the
right
of
the
curves
.
8
Courtesy of NationalSwitchgear.com
GEK
-
7351
These
curves
were
determined
by
tests
performed
with
no
voltage
applied
to
the
relay
before
the
fault
was
applied
.
That
is
the
steady
state
curve
.
While
the
dynamic
curves
were
obtained
with
full
rated
voltage
appplied
to
the
relay
before
the
fault
was
applied
.
MEMORY
ACTION
The
dynamic
curves
of
fig
.
12
show
the
effect
of
memory
action
in
the
unit
which
maintains
the
polarizing
flux
for
~
few
cycles
following
the
fault
.
This
memory
action
is
particularly
effective
at
low
voltage
levels
of
current
.
The
steady
state
curve
shows
that
the
unit
will
not
see
a
fault
at
zero
percent
of
the
relay
setting
regardless
of
the
tap
setting
.
Under
dynamic
conditions
when
memory
action
i s
effective
,
when
I
is
greater
than
2.53
amperes
.
TRANSIENT
OVERREACH
The
operation
of
the
mho
unit
under
transient
conditions
at
the
inception
of
a
fault
is
important
because
the
relay
is
normally
connected
so
that
the
MHO
contacts
will
trip
a
circuit
breaker
independently
of
any
other
contacts
.
The
impedance
characteristic
of
Fig
.
11
and
the
steady
-
state
curves
of
Fig
.
12
represent
steady
-
state
conditions
.
If
the
fault
current
contains
a
D
-
C
transient
,
the
unit
may
close
its
contacts
momentarily
even
though
the
impedance
being
measured
is
slightly
greater
than
the
calculated
steady
-
state
reach
.
This
overreaching
tendency
will
be
a
maximum
when
a
fault
occurs
at
the
one
instant
in
either
half
-
cycle
which
produces
the
maximum
D
-
C
offset
of
the
current
wave
.
The
maximum
transient
overreach
of
the
MHO
unit
will
not
exceed
5
percent
of
the
steady
-
state
reach
for
line
angles
up
to
85
degrees
.
OPERATING
TIME
The
operating
time
of
the
MHO
unit
is
determined
by
a
number
of
factors
such
as
the
basic
minimum
reach
setting
of
the
unit
,
fault
current
magnitude
,
ratio
of
fault
impedance
to
relay
reach
,
and
magnitude
of
relay
voltage
prior
to
the
fault
.
The
curves
in
Fig
,
13
are
for
the
condition
of
rated
volts
prior
to
the
fault
.
Time
curves
are
given
for
four
ratios
of
fault
impedance
to
relay
reach
setting
.
In
all
cases
,
the
M
10
taps
were
in
the
100
percent
position
and
the
angle
of
maximum
torque
was
set
at
75
°
TA
-
VERNIER
ADJUSTMENT
FOR
LOW
TAP
SETTINGS
The
input
leads
to
the
tapped
auto
-
transformer
are
normally
set
at
100
percent
,
but
for
applications
on
lines
with
a
high
secondary
line
impedance
,
where
the
tap
leads
would
be
set
at
a
low
percentage
,
the
input
connections
can
be
varied
by
a
vernier
method
to
obtain
a
closer
setting
.
For
example
,
if
the
desired
first
-
zone
reach
is
4.5
ohms
and
the
basic
minimum
reach
setting
of
the
unit
is
3
ohms
,
with
the
input
setting
on
100
percent
,
the
tap
leads
would
be
:
=
100
(
3
)
Tap
Setting
66.7
percent
4.5
This
desired
-
reach
setting
can
be
made
within
0.45
percent
accuracy
by
means
of
the
67
percent
However
,
if
the
desired
firsr
zone
reach
were
28.5
ohms
,
the
output
tap
setting
would
be
:
tap
.
100
(
3
)
=
10.5
percent
2875
The
nearest
output
tap
would
be
11
percent
which
is
4.2
percent
off
the
desired
value
.
To
correct
this
,
the
input
leads
can
be
shifted
to
95
percent
,
in
which
case
,
the
output
would
be
:
95
(
3
)
=
10
percent
28.5
BURDENS
CURRENT
CIRCUITS
The
maximum
current
burden
imposed
on
each
current
transformer
at
5
amperes
and
60
cycles
is
listed
below
:
AMPS
CYCLES
R
P
.
F
.
X
w
.
V
A
5
60
.
089
.
019
.
98
2.22
2.5
9
Courtesy of NationalSwitchgear.com
GEK
-
7351
This
data
is
for
the
3
ohm
basic
reach
tap
settings
,
setting
will
be
lower
.
The
burden
for
the
1.5
and
the
0.75
ohm
tap
POTENTIAL
CIRCUITS
The
maximum
potential
burden
imposed
on
each
potential
transformer
at
120
volts
and
60
cycles
is
listed
below
.
IK
CIRCUIT
P
7
F
7
WATTS
R
X
Polarizing
1300
-
J
680
0.89
8.7
9.8
Restraint
4.5
3200
JO
1.0
4.5
The
potential
burden
of
the
mho
unit
is
maximum
when
the
restraint
tap
is
set
at
100
%
.
The
restraint
circuit
burden
and
hence
the
total
burden
will
decrease
when
the
restraint
tap
setting
is
less
than
100
%
.
The
potential
burden
at
tap
settings
less
than
100
%
,
can
be
calculated
from
the
following
formula
.
Tap
Setting
VA
=
(
a
+
Jb
)
+
(
c
+
jd
)
The
terms
(
a
+
Jb
)
(
c
+
Jd
)
represent
the
burdens
of
the
mho
unit
potential
circuit
expressed
in
watts
and
vars
with
their
taps
on
100
%
,
The
values
for
these
terms
are
as
shown
below
.
100
TERM
CIRCUIT
TERM
(
WATTS
+
J
VARS
)
(
WATTS
±
J
VARS
)
(
4.5
+
JO
)
(
8.7
+
J
4.5
)
(
a
+
Jb
)
(
c
+
Jd
)
RESTRAINT
POLARIZING
MECHANICAL
ADJ
.
Check
Points
Mh
Unit
Rotating
Shaft
End
Play
Contact
Gap
Contact
Wipe
(
N
.
O
.
Contacts
)
.
010
-
.
015
inch
.
030
-
.
035
inch
.
003
-
.
005
inch
SERVICING
The
phase
shifter
phase
angle
meter
method
of
testing
the
CEY
53
A
relay
.
Connect
the
relay
per
Figure
14
except
(
C
)
to
stud
3
(
D
)
to
stud
8
and
jumper
studs
6
and
7
.
Directional
Tests
A
.
1
.
Put
the
reach
taps
int
he
1.5
ohm
position
.
2
.
Set
current
for
5
amperes
and
the
voltage
for
120
volts
.
3
.
Set
the
phase
angle
at
285
degrees
(
75
degrees
lag
)
.
4
.
Reduce
the
voltage
to
0
.
Vary
the
current
from
0
to
60
amperes
,
the
unit
should
develop
slight
opening
torque
.
Adjust
the
core
if
this
test
fails
,
refer
to
figure
15
.
The
core
can
be
rotated
360
degrees
without
having
to
loosen
any
part
of
the
assembly
.
This
adjustment
is
done
by
using
a
special
core
adjusting
wrench
(
Cat
.
No
.
0178
A
9455
Pt
.
1
)
which
fits
only
octagon
nut
D
in
figure
15
.
5
.
Set
the
voltage
to
2.0
volts
and
current
to
3
amperes
and
adjust
the
control
spring
until
the
unit
just
closes
.
Then
increase
the
current
to
60
amperes
and
the
contact
should
remain
closed
.
10
Courtesy of NationalSwitchgear.com
GEK
-
7351
SERVICING
Reach
And
Angle
Of
Maximum
Torque
.
B
.
Connect
per
figure
14
Table
1
.
Set
voltage
at
45
volts
.
Set
the
restraint
taps
on
50
percent
.
Set
the
reach
Ups
in
the
1.5
ohm
position
.
1
.
2
.
4
.
TABLE
I
TABLE
II
CONNECT
TO
STUD
CONNECT
TO
STUD
A
3
A
3
4
4
B
B
5
C
7
C
D
D
6
8
SERVICING
1
.
Set
voltage
at
45
volts
and
current
at
15
amperes
.
2
.
Set
the
phase
shifter
so
that
the
phase
angle
meter
reads
75
degrees
lag
(
285
degrees
lead
)
.
3
.
Adjust
Rll
to
obtain
the
reach
at
45
volts
and
15
amps
(
14.6
-
15.4
)
at
75
degrees
lag
(
285
degrees
lead
)
.
4
.
To
check
the
angle
of
maximum
torque
,
set
the
phase
angle
meter
30
degrees
either
side
of
the
angle
of
maximum
torque
and
adjust
the
reactor
X
-
ll
to
obtain
the
pickup
currents
as
shown
in
the
table
below
.
0
/
METER
READINGS
STUD
3
-
4
VOLTAGE
MHO
UNIT
/
MAX
.
TOR
.
TEST
ANGLES
PICKUP
AMPS
75
°
45
and
105
°
315
°
and
255
°
Lag
j
_
Lead
/
45
Volts
16.5
-
18.2
285
°
Adjust
X
-
ll
until
the
pickup
amps
are
equal
and
in
limits
As
above
for
both
test
angles
as
shown
in
the
chart
.
5
.
Recheck
the
angle
of
maximum
torque
as
in
para
.
3
above
.
Cross
adjust
para
.
3
and
5
until
the
relay
reach
and
angle
of
maximum
torque
is
in
limits
without
any
further
adjustments
.
6
.
Connect
relay
per
table
II
of
Fig
.
14
and
check
that
the
reach
is
within
+
-
3
percent
of
the
limits
as
test
above
in
para
.
3
.
7
.
Repeat
Direction
Test
(
do
not
adjust
control
spring
)
.
If
core
required
adjustment
,
repeat
tests
.
8
.
Check
of
other
basic
minimum
taps
as
follows
:
PHASE
ANGLE
SETTING
RESTRAINT
PICKUP
CURRENT
TAP
VAB
TAP
285
°
.
75
25
45
14.2
-
15.8
14.2
-
15.8
3
2850
100
45
Clutch
1
.
Short
No
.
1
leads
together
.
2
.
Connect
per
Figure
14
except
connect
C
to
5
and
D
to
8
,
jumper
6
to
7
.
3
.
Apply
120
volts
and
the
clutch
must
slip
between
26
and
45
amperes
.
11
Courtesy of NationalSwitchgear.com
GEK
-
7351
TESTING
WITH
THE
X
+
R
EQUIPMENT
PORTABLE
TEST
EQUIPMENT
To
eliminate
the
errors
Which
may
result
from
instrument
inaccuracies
and
to
permit
testing
the
mho
units
from
a
single
phase
A
-
C
test
source
,
the
test
circuit
shown
in
schematic
form
in
16
is
reco
-
mmended
.
Sp
is
the
fault
switch
,
and
+
jX
|
_
is
the
impedance
of
the
line
section
for
which
the
relay
is
being
tested
.
The
autotransformer
TA
,
which
is
across
the
fault
switch
and
line
impedance
,
is
tapped
in
10
percent
and
1
percent
steps
so
that
the
line
impedance
RL
+
jX
may
be
made
to
appear
to
the
relay
very
nearly
as
the
actual
line
on
which
the
relay
is
to
be
used
.
This
is
necessary
since
it
is
not
feasible
to
provide
the
portable
test
reactor
\
and
the
test
resistor
with
enough
taps
so
that
the
combination
may
be
made
to
match
any
line
.
For
convenience
in
field
testing
,
the
fault
switch
and
tapped
autotransformer
of
Fig
.
17
have
been
arranged
in
a
portable
test
box
,
Cat
.
No
.
102
L
201
,
which
is
particularly
adapted
for
testing
directional
and
distance
relays
.
The
box
is
provided
with
terminals
to
which
the
relay
current
and
potential
circuits
as
well
as
the
line
and
source
impedances
may
be
readily
connected
.
For
a
complete
.
description
of
the
test
box
the
user
is
referred
to
GEI
-
38977
.
To
check
the
calibration
of
the
mho
units
,
it
is
suggested
that
the
portable
test
box
,
Cat
.
No
.
102
L
201
;
portable
test
reactor
,
Cat
.
No
.
6054975
;
and
test
resistor
,
Cat
.
No
.
6158546
be
arranged
with
Type
XLA
test
plugs
according
to
Fig
.
17
.
These
connections
of
the
test
box
and
other
equipment
are
similar
to
the
schematic
connections
shown
in
Fig
.
16
except
that
the
Type
XLA
test
plug
connections
are
now
included
.
The
angle
may
be
checked
by
using
the
calibrated
test
resistor
in
combination
with
various
reactor
taps
.
The
calibrated
test
resistor
taps
are
pre
-
set
in
such
a
manner
that
when
used
with
12
and
6
ohm
taps
of
the
specified
test
reactor
,
impedance
at
75
degrees
and
45
degrees
respectively
will
be
available
for
checking
the
mho
unit
at
the
75
degree
and
45
degree
positions
.
The
mho
unit
ohmic
reach
at
the
zero
degree
position
may
be
checked
by
using
the
calibrated
test
resistor
alone
as
the
line
impedance
.
The
calibrated
test
resistor
is
supplied
with
a
data
sheet
which
gives
the
exact
impedance
and
angle
for
each
of
the
combinations
available
.
The
test
-
box
autotransformer
percent
tap
for
pickup
at
a
particular
angle
is
given
by
:
1.5
)
cos
(
9
-
0
)
M
Tap
%
)
ZL
(
100
)
(
10
)
%
Tap
=
where
:
0
=
Angle
of
maximum
torque
of
mho
unit
0
=
Angle
of
test
impedance
Z
|
_
.
ZL
=
The
75
°
,
45
°
,
or
(
P
impedance
value
from
calibrated
test
resistor
data
sheet
.
M
=
Mho
Unit
restraint
tap
setting
.
ELECTRICAL
TESTS
DRAWOUT
RELAYS
GENERAL
Since
all
drawout
relays
in
service
operate
in
their
case
,
it
is
recommended
that
they
be
tested
in
their
case
or
an
equivalent
steel
case
.
In
this
way
any
magnetic
effects
of
the
enclosure
will
be
accurately
duplicated
during
testing
.
A
relay
may
be
tested
without
removing
it
from
the
panel
by
using
a
12
XLA
13
A
test
plug
.
This
plug
makes
connections
only
with
the
relay
and
does
not
disturb
any
shorting
bars
in
the
case
.
Of
course
,
the
12
XLA
12
A
test
plug
may
also
be
used
.
Although
this
test
plug
allows
greater
testing
flexibility
,
it
also
requires
C
.
T
.
shorting
jumpers
and
the
exercise
of
greater
care
since
connections
are
made
to
both
the
relay
and
the
external
circuitry
.
POWER
REQUIREMENTS
GENERAL
All
alternating
current
operated
devices
are
affected
by
frequency
.
Since
non
-
sinusoidal
waveforms
can
be
analyzed
as
a
fundamental
frequency
plus
harmonics
of
the
fundamental
frequency
,
it
follows
that
alternating
current
devices
(
relays
)
will
be
affected
by
the
applied
waveform
.
Therefore
,
in
order
to
properly
test
alternating
current
relays
it
is
essential
to
use
a
sine
wave
of
current
and
/
or
voltage
.
The
purity
of
the
sine
wave
(
i
.
e
.
its
freedom
from
harmonics
)
cannot
be
expressed
as
a
finite
number
for
any
particular
relay
,
however
,
any
relay
using
tuned
circuits
,
R
-
L
or
12
Courtesy of NationalSwitchgear.com
GEK
-
7351
RC
networks
,
or
saturating
electromagnets
(
such
as
time
overcurrent
relays
)
would
be
essentially
affected
by
non
-
sinusoidal
wave
forms
.
Similarly
,
relays
requiring
dc
control
power
should
be
tested
using
dc
and
not
full
wave
rectified
power
.
Unless
the
rectified
supply
is
well
filtered
,
many
relays
will
not
operate
properly
due
to
the
dips
in
the
rectified
power
.
Zener
diodes
,
for
example
,
can
turn
off
during
these
dips
.
As
a
general
rule
the
dc
source
should
not
contain
more
than
5
%
ripple
.
RECEIVING
,
HANDLING
AND
STORAGE
These
relays
,
when
not
included
as
a
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
substained
in
transit
.
If
injury
or
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
injured
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
.
PERIODIC
CHECKS
AND
ROUTINE
MAINTENANCE
In
view
of
the
vital
role
of
protective
relays
in
the
operation
of
a
power
system
it
is
important
that
a
periodic
test
program
be
followed
.
It
is
recognized
that
the
interval
between
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
INSTALLATION
PROCEDURE
be
checked
at
an
interval
of
from
one
to
two
years
.
CONTACT
CLEANING
For
cleaning
relay
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
it
will
clean
off
any
corrosion
throughly
and
rapidly
.
Its
flexibility
insures
the
cleaning
of
the
actual
points
of
contact
.
Do
not
use
knives
,
files
,
abrasive
paper
or
cloth
of
any
kind
to
clean
relay
contacts
.
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
Company
,
specify
quantity
required
,
name
of
the
part
wanted
,
and
the
complete
model
number
of
the
relay
for
which
the
part
is
required
.
INSTALLATION
PROCEDURE
LOCATION
The
location
of
the
relay
should
be
clean
and
dry
,
free
from
dust
,
excessive
heat
and
vibration
,
and
should
be
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
8
.
Immediately
upon
recepit
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
*
If
the
examination
or
test
indicates
that
readjustment
is
necessary
,
refer
to
the
section
on
Servicing
.
13
Courtesy of NationalSwitchgear.com
GEK
-
7351
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
the
screws
are
tight
.
MECHANICAL
INSEPCTION
1
.
Check
the
mechanical
adjustments
on
page
10
.
There
should
not
be
any
noticable
friction
in
the
rotating
structure
of
the
unit
or
in
the
target
/
seal
-
in
unit
.
2
.
3
.
Check
the
location
of
contact
brushes
on
the
cradle
and
the
brushes
and
the
shorting
bars
on
the
case
blocks
according
to
the
internal
connections
diagram
.
14
Courtesy of NationalSwitchgear.com
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CEY
53
A
Response
Curve
Over
A
Range
Of
38
To
70
Hz
16
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7351
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17
Courtesy of NationalSwitchgear.com
GEK
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7351
CONNECTING
PLUG
MAIN
BRUSH
CONNECTING
BLOCK
J
AUXILIARY
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CEY
53
A
Relay
(
Front
View
)
18
Courtesy of NationalSwitchgear.com
GEK
-
7351
PANEL
LOCATION
SEMI
-
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(
6209273
(
5
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Outline
And
Panel
Drilling
Dimensions
For
The
CEY
53
A
Relay
19
Courtesy of NationalSwitchgear.com
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.
i
.
-
!
•
~
r
i
i
E
12
i
t
C
21
i
:
\
i
t
*
-
i
i
;
7
*
*
OPER
.
i
i
*
•
*
i
>
:
t
T
(
l
-
f
B
i
i
E
i
f
i
i
i
1
<
POL
.
POL
.
FIG
.
9
(
0227
A
2544
-
0
)
Schematic
Connections
Of
The
Mho
Unit
In
The
CEY
53
A
Relay
IX
/
/
/
.
i
i
,
\
It
°
<
l
Zp
1
\
\
ZT
«
-
TRANSACTOR
TRANSFER
IMPEDANCE
Zr
-
IMPEDANCE
BETWEEN
RELAY
&
FAULT
E
—
PHASE
-
TO
-
PHASE
VOLTAGE
(
°
<
IZf
)
T
xTAPSETTING
IN
PERCENT
v
\
0
-
TRANSACTOR
ANaE
IR
10
(
0227
A
2467
-
1
)
Graphical
Presentation
Of
Mho
Unit
Operating
Principles
FIG
.
20
Courtesy of NationalSwitchgear.com
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