GE CEYG51A User manual

GEK-26423D
INSTRUCTIONS
GROUND
DISTANCE
RELAY
TYPE
CEYG51A
GE
Protection
and
Control
205 Great
Valley Parkway
Maivern,
PA
19355-1337

GEK-26423
CONT
E
NTS
PAGE
iNTRODUCTION
3
APPLICATION
3
RATINGS
4
Contacts
4
OPERATINO
PRINCIPLES
5
CHARACTERISTICS
5
Pickup
6
Operating
Time
6
Burden
6
CALCULATION
OF
SETTINGS
7
CONSTRUCTION
9
RECEIVING,
HANDLING
AND
STORAGE
9
ACCEPTANCE
TESTS
10
Visual
Inspection
10
Mechanical
Inspection
10
Electrical
Tests
10
iNSTALLATION
PROCEDURE
11
Relay
Settings
11
Mechanical
Checks
11
Electrical
Checks
11
PORTABLE
TEST
EQUIPMENT 11
SERVICING
14
Restraint
Circuit
Angle
Adjustment
15
Directional
Characteristic
15
Maximum
Torque
Angle
15
Pickup
15
Clutch
Adjustment
15
RENEWAL
PARTS 16
APPENDIX
I
MINIMUM
PERMISSIBLE
REACH
SETTING
FOR
THE
CEYG51A
17
No
Zero
Sequence
Current
Compensation
17
With
Zero
Sequence
Current
Compensation
18
APPENDIX
II
MAXIMUM
PERMISSIBLE
REACH
SETTING
FOR
THE
CEYGS1A
18
No Zero
Sequence
Current
Compensation
18
APPENDIX
III
MAXIMUM
PERMISSIBLE
REACH
SETTING
FUR
THE
CEYGS1A
20
With
Zero
Sequence
Current
Compensation
20
2

GEK-26423
GROUND
DISTANCE
RELAY
CEYG51A
RELAY
INTRODUCTION
The
CEYGS1IX
is
a
three phase,
high
speed,
single zone,
mho
type, directional
distance
ground
relay.
It
consists
of
three
single-phase
units in
one
L2—D
case
with facilities
for
testing
one
unit at
a
time. One
target
and
seal-in
unit
provides
indication
of
operation
for
all
three
distance
units.
The
transient
over
reach characteristic
of
the
CEYG51A
relay
has
not
been
limited
to
the
point where
it
is
suitable
for use
as
a
first-zone
relay.
The
relay waS
specifically
designed
for
use
as
an
overreaching
device in
directional
comparison
and
transferred
tripping
schemes.
Figure
3
shows
the
internal
connections.
APPL
I
CAT
ION
The
CEYG51A
ground
mho
relay is
applied
as
the
primary
ground
relay in
directional
comparison
and
per
missive
overreaching
transferred
tripping
schemes,
employing
separate
primary
and separate
backup
protec
tion.
The
ground
rnho
units
of
the
CEYG5IA
relay
are
specifically
designed
to
detect
single
phase to
ground
faults.
To
this end
they
are
supplied
with
quadrature voltage
polarization.
Thus,
the
polarizing
voltage
will
be
quite
high
and
the
relay will have
a
high
operating
torque level
even
on
very
close
in
line to
ground
faults.
For
this
reason, these
units
are
not provided
with
memory action.
These
ground
niho
units
will
also
respond
to
three
phase
faults.
If
this
is
objectionable,
the
relay
can
be
made
unresponsive
to
any
faults not
involving
ground simply
by
adding a
non—directional zero
sequence
fault detector.
The
ground
mho
units
are
provided
with separate
current
circuits
for
zero
sequence
current
compensa
tion.
A
tapped
auxiliary
current
transformer
is
used
to
obtain
the
proper
ratio
of
compensation.
When
zero
sequence
current
compensation
is
used, the
ground
iiho
unit has
essentially
the
same
reach
on
single
phase to
ground
faults
as
on
three
phase
faults.
If
zero
sequence compensation
is
NOT
used, the
ground
niho
unit
reach
is
considerably foreshortened
on
single
phase
to
ground
faults.
See
Appendix
I
for
the
minimum
permissible
reach
settings
under
both
conditions.
In
directional
comparison
schemes,
two
CEYG51A
relays connected
back—to-back
are
required
at
each
terminal.
These
relays
operate
in
conjunction
with
a
carrier
channel to
provide
high
speed
protection
against
all
single
phase to
ground
faults
in
the
protected
line
section.
One
relay
acts to
Stop
carrier
and
trip
for
internal
faults
while
the
other
initiates
carrier
blocking
on
external
faults.
if
zero
sequence
current
compensation
is
used
on
the
carrier
stopping
and
tripping
units,
it
should
also
be
used
on
the
carrier
starting
units.
This will
facilitate
the
unit
settings
and
insure
that
both
units
that
must
coordinate
will
be
operating
on
the
same
torque
level,
in
any
event,
the
carrier
starting
unit
should
be
set as
sensitively
as
possible.
This
will
tend
to
increase
security
since
the
presence
of
a
carrier
signal
will
block
tripping.
In
permissive
overreaching
transferred
tripping
schemes,
one
CEYG51A
relay
is
required
at
each ter
minal.
It
acts
as
a
combined
transferred
trip
initiating
and
a
permissive
relay for
ground
faults in
the
protected
line
section.
The
choice
of
whether or
not to
use
sequence
current
compensation
depends
upon
the
protected
line
length
and
system
conditions.
When zero
sequence
current
compensation
is
NOT
used,
the
ground mho
unit
reach
required
may
be
about
2
to
3
times
the
positive
sequence
impedance
of the
line
in
order
to provide
the proper
coverage.
This
then
tends to
make
the
ground mho
unit
more
sensitive
to
operation
on
load
con
ditions
or
on
power
swings.
The
use
of
zero
sequence
current
compensation
reduces
the
necessary
ground
mho unit
reach
setting
to
approximately
1.25
times the
positive
sequence
impedance
of
the
line
and,
thus,
minimizes
its
response
to
load
or
power
swings.
This is
true
provided
there
is
little
or
no
mutual
im
pedance
present
from
a
parallel
line.
These
nstroctions
do
not purport
to
cover
all
details
or
variations
in
equipment
nor to
provide
For
eeerc poss:ble
contanJencj to
be
met in
connection
with
installation,
operation
or maintenance.
Should
furtn-r
information be
desired
or
should
particular
problems
arise
which are
not
covorci
sufficientlq
for
tn
purchaser’s
purposes,
the matter
should be
referred
to the General
Electric
Ccmpant.
To
he extent
,eau:red
the
products
descrrhed herein meet applicable
?.ESI, IEEE and
.S1IMA
standards;
:ot
sucn
-scranc.
s
;iven with respect
to
local codes and ordinances
because
he; varo rcatly.

GEK-26423
Whether
or
not
zero
sequence
current
compensation
is
used,
the
ground
mho
units
may
be
subject to
in
correct
operation
on
ground
faults immediately
behind
the
relay
terminals.
This will
be
dependent
upon
the
line
impedance
and
system
conditions.
It
nay
he
necessary
to
1 mit
the
mho
unit reach
setting in
order
to
avoid
this
false
tripping.
Appendix
II
gives
the
limiatations
of
the
mho
unit
reach
setting
when
zero
sequence
current compensation
is
NOT
used
Appendix
ill
gives
the
limitdtions
of
the
inho
unit
reach
setting
when
zero
sequence
current
compensation
is
used.
The
system
conch
tions
which
requ
cc
the
1
im
tdtion of
the
uho
unit
reach,
as
described
by
Appendices
II
and
Ill
,
are
rather
unusual
.
They
occur
when
the
zero
sequence
current
contribution
over
the
line
to
a
fault
behind
the
relay is
larger
than the
positive
sequence
current
contribution.
If
the
reach of
the
unfaulted
phase
units
ii
the
non-trip
direction
is
an
application
limitation,
a
zero
sequence
directional
overcurrent
relay
(CFPG16A) nay
be
used
to
supervise
the
CEYG51
operation.
This
will
permit
tripping
only
when
the
fault is
in
the
forward
direction.
The
external
connections
are
shown
in
Figure
4.
Since the
CEYG51A
is
an
extended
range
relay
with
three
basic
minimum
reach
settings,
the
best overall
performance
will
be
obtained
if
the
highest
basic
minimum
reach
tap
setting
that
will
accommodate
the
de
sired setting
is
used.
RATINGS
The
Type
CEYG5IA
relays
covered
by
these
instructions
are
available
with
potential
circuits
rated
for
operation
on
wye-wye
connected
potential
transformers
which
supply secondary
voltage
of
120
volts
phase-
to-phase.
Current
coil
ratings
and
ohmic
ranges
are
as
tabulated
below:
BASIC
MIN.
RANGE
CONTIN.
ONE
SEC.
OHMIC
REACH
OHMIC
REACH
CURRENT
RATING
CUR.
RATING
(0-N
OHMS)
(0-N
OHMS)
AMPERES
—
AMPERES
1/2/3
1
- 30
5
225
0.5/1.0/1.5
0.5
- 15
5
225
The
ohmic
reach
is
at
the
angle
of
maximum
torque of
60
degrees
lag,
and
can
be
adjusted
in
5
percent
steps
by
means
of
a
tapped
autotransformer.
It
will
be
noted
that
three
basic
minimum
reach
settings
are
listed
for
the
mho
units.
Selection
of
the
desired
basic
minimum
reach
is
made
by
means
of
links
on
terminal
boards
located
on
rear
of
the
relay.
The
positions
of
the
two
sets
of
links,
(for
each
N
unit), each
identified
as
A-B
determine
the
minimum
ohmic
reach
setting
as
follows:
MINIMUM
OHMIC
REACH
SETTING
(OHM
PHASE-TO-NEUTRAL)
A
+
B
CONTACTS
The
main
circuit-closing
contacts
of
the
re1a
will
close
and
carry
30
amperes
DC
momentarily
for
tripping
duty
at
control voltages
of
250V
DC
or
less.
The
circuit
breaker
trip
coil
should,
however,
always
by
opened
by
an
auxiliary
switch or
other
suitable
means.
If
the
tripping
current
exceeds
30
amperes,
a
tripping
relay
should
be
used.
The
current
carrying
rating
of
the
main
contacts
is
determined
by
the
tap
setting
of
the
seal—in
coil
as
shown
in
Table
I
TABLE I
TARGET AND
SEAL-IN
UNIT
2.0 0.6
0.2
——
Amp
Tap
A;np
Tap
—
Amp
Tap
I—C
Resistance
0.13
Ohms
0.6
Ohms
7
Ohms
Carry
Continuously
3.5
Amps
1.0
Amps
0.35
Amps
Carry
30
Amps
for
4
Secs.
0.5
Secs.
Carry
10
Amps
for
0.2
Secs.
4

GEK-26423
The
normally
closed contacts
between
terminals
19
and
20
will close,
carry continuously,
or
interrupt
0.3
amperes
in
non—inductive
circuits
up
to
250V
DC.
OPERATING
PRINCIPLES
The
inhu
type
units in
the
CEYGS1A
relay
are
of
the
four-pole
induction-cylinder
construction (see
Fig.
6)
with
schematic
connections
as
shown
in
Fig.
3.
The
two
side poles,
which
are
energized
by
the
phase-to-phase
voltage
in
quadrature
with
the
phase-to—neutral
voltage of
the
protected
phase,
produce
the
polarizing
flux. The
flux
in
the
front
pole,
which is
energized
by
a
percentage
of
the
phase-to-neutral
vol
tdye
of
the
protected
phase,
interacts
with
the polarizing
flux
to produce
restraint
torque.
The
flux
in
the
rear pole,
which is
energized
by
the
line
current
of
the
protected
phase,
interacts
with the
polar
izing
flux
to
produce
operating
torque.
The
torque
at
the
balance
point
for
the
phase A starting
unit
can,
therefore,
be
expressed
by
the
following
equation:
Torque =
0
=
KIaEbc
COS
((
-30)
— TEEb’
sin
B
(1)
where:
K
design
constant
=
Phase—A-to-neutral
voltage at
the
relay location
Ebc’
=
Phase
B
to
Phase C voltage
(Eb -
E)
at
the
relay
‘a
=
Phase
A
current,
at
the
relay
location
B
=
Angle
by
which
Ea
leads
Ebc’
(900
for
balanced
3-phase
condition)
T
=
Restraint
tap
setting
=
Angle
by
which
‘a
leads
Ebc
CHARACTER
1ST
1 CS
The
operating
characteristics
of
the
mho
units
in
the
CEYG51A
relay
may
be
represented
on
the
R—X
impedance
diagram as
shown
in
Fig. 7.
It
should
be
noted
that
these
steady-state
characteristics
are
for
rather
specific
fault
conditions
described
below:
The
inho
unit
has
a
circular
characteristic
which
passes
through
the
origin
of
the
R-X
diagram.
The
diameter
passing through
the
origin
defines the
angle
of
maximum
torque
of
the
unit, which
occurs
when
line
current
(Ia
for
example)
leads
the
quadrature
polarizing
voltage
(Ebc
for example)
by
30°.
Since
there
is
essentially
no
phase
shift
in
the
line—to—neutral
voltage
for a single-phase-to-ground
fault,
this
maximum
torque
angle
(i.e.
maximum
reach
angle)
occurs when
the
line current
lags
the
phase—to-neutral
voltage
by
600,
which
is
the
condition represented
in
Fig.
8.
The
diameter
of
the
impedance
circle
would nomally
be
considered
as
the
ohmic
reach
of
the
unit,
which
would
be
the
basic
minimum
reach with
the
E
tap leads
on
100
percent.
However,
if
the
niho unit
is
not
compensated
it
is
not
an
accurate
distance
measuring
until
except on
3-phase
faults,
or
for
the
special
case
of
single-phase—to-ground
faults
where the
zero-sequence
impedance
to
the
fault
is
equal to
the
positive
sequence
impedance
to
the
fault.
Instructions
are
given
in
Appendices
II
and
III
for
selecting
a
reach setting.
The
ohmic
reach of
the
mho
unit
can
be
extended
by
reducing the
percentage
of
the
fault voltage
applied
to
the
restraint
circuit,
that
is
by
setting
the
E 2
tap
leads on
a
lower
percentaoe
position
on
the
tap block.
(Zi)
100
Ohmic
ReQch
=
2
E
Tap Setting
()
(5)
5

GE
K—2
64
23
The
ohmic
reach
obtained
from
equation
(5)
assumes
that line
angle
and
maximum
torque
angle
are
equal
(600).
The
reduced
reach
at
line
angles
other
than
600
can
be
obtained
by
multiplying
the
reach
obtained
from
equation
(5)
by
cos
(60-0)
where
0
is the
line
angle.
PICKUP
The
operating
torque
will
close
the
contacts
when
the
fault
current
is
in a
certiri
direction
and
of
ufficient
magnitude to
overcome
the
restraint
torque.
The
operating
torque
on
3-phase
faults
is
a
maxi
mum
for
fault
currents
which
lag
the
unity
power
factor
position
by
60
degrees
and
is reliable
down
to
one
percent
voltage
with
currents
as
tabulated
below:
MINIMUM OHMIC
REACH
SETTING
CURRENT
RANGE FOR
RELIABLE
OPERATION
(0-N
OHMS)
0.5
36 -
60
1
18-60
1.5
12
—
60
2
9
-
60
3
6
-
60
On
single-phase-to-ground
faults
the
quadrature
polarizing potential
will
remain
quite
high
with
the
result
that
the
relay
will
operate
at
considerably
less
current
than
tabulated.
For
example,
with
a
one
percent
restraint
voltage
and
120
volts
polarizing
the
unit
will
operate
with
less
than 1
ampere
operating
current
for
the
3-ohm
minimum
reach
setting.
OPERATING
TIME
For
typical
operating
time
characteristics
see
Figure
13A
and
138.
BURDEN
The
burden
imposed
on
the
potential
transformers
by
the
type
CEYG51A
relay
with
the
restraint
tap
set
at
100
percent
is
as
given
below:
Basic
Rated
Polarizing
Circuit
Restraint Circuit
Ohms
Freq
V
Watts
Vars
VA
Volts
Watts
Vars
VA
1
-
30 60
120
10.1
8.88
13.5
70
2.7
4.0
4.8
0.5
-
15
60
120
10.1
8.88
13.5
70
0.9
1.6
1.8
1
-
30 50
120
8.41
7.38
11.2
70
1.7
3.0
3.4
I-f
the
restraint
tap
is
reduced,
the
burden
of the
restraint
circuit
is
given
by
the
following
equation:
VA
=
Watts
*(2
+
.
VARS(i”)
where
Watts
Restraint
circuit
watts
from
table
above.
VARS
=
Restraint
circuit
Vars
from
table
above.
T
Tap
in
percent.
6

GEK-26423
Basic Rated
3-4, 5-6,
or
7-8
Circuit
9-10
Circuit
Ohms
Freq.
I
X
2 1
R
X
Z
1 - 3D
60 5
0.070
0.040
0.080
5
0.210
0.120
0.240
0.5
- 15
60
5
0.007
0.005 0.008
5
0.021
0.013 0.024
1
- 30 50
5
0.058 0.033
0.067
5 0.175
0.100 0.200
NOTE: Above
data is
for
the
mho
units set
on
their
maximum ohmic
reach taps.
The
burden
for
the
lower
reach tap
settings
will be less
than the
tabulated
burdens.
CALCULATION OF
SETTINGS
In
applying
the relay
to a
particular
line and system, the
limitations
outlined
under
APPLICATION
fre
quently do not
materialize.
Therefore,
it
is
recommended that
the initial
calculations
of
1
and 2
below
be followed to
determine
what
final
calculations
may be necessary
and how
the relay
may be
applied.
1.
Determimimme
if zero
sequence
current
compensation
is required.
This
will depend
upon
on
evaluation
of
the
necessary
rnho
unit tap
settings
and the relation
of the
resulting
mho
characteristic
with
the
line
power
loadings
and power
swings. See
Appendix
I,
equations
‘b
and
I.
2.
Determine
if there
is a
limitation
in
the
application
for incorrect
operation
on
faults
behind
the
relay
terminal.
a. When
zero sequence
current
compensation
is
t.{Qi
used:
if Co is
equal
to
or less
than
C, no
further
evaluation
need be
made.
See
Appendix II,
equations
ha, hib
and
tIc.
b. When
zero
sequence current
compensation
is used: if
(3K
+
1)
Co is
equal to
or
less
than C,
no
further
evaluation
need
be made. See
Appendix
III,
equations
lIla,
hlIb
and
Ihic.
c. If
neither
a
nor b
above
is
applicable,
evaluate
the
equations
of either
Appendix
II
or
III to
determine
if it
is
necessary
to use
the zero
sequence
directional
overcurrent
supervising
re
lay,
Type
CFPH16A.
The
following
calculations
are made
as
an
example of
determining
the
actual tap
settings
to
be
used.
Consider the
protected
line to be
between
breakers
A and B on
the
portion of a
system
shown
in Fig.
5.
Assume the
following
characteristics:
Z 1 = 24.0
/790
primary
ohms
= 72.0
/750
primary
ohms
14.4
/75°
primary
ohms
CT Ratio
600/5
PT
Ratio
1200/1
Secondary
Ohms
= CT Ratio
x
Primary
Ohms
PT
Ratio
21
= 2.4
/79°
= 0.47
+ j2.36 secondary
ohms
Z 0 ’ = 7.2
/75°
= 1.9
+
j6.95
secondary
ohms
Zom
1.4
/75°
=
0.36 + jI.35
secondary ohms
Checking
Appendix
I
first
to
establish
the maximum
tap
setting
that would
still
permit
the
CEYG5IA
at
breaker
A to
detect
a
single
phase to
ground fault
(F2)
at the remote
bus,
Equation
lb
should
be
used.
The
burdens imposed
on
the
current
transformers
by
the current
circuits are
given below:
7

GEK-26423
Assume
for
this
fault
at
F2
that
a
system
study
yields
the
following
quantities.
C 0
=
0.17
C
=
0.20
=
13.7
secondary
amperes
based
on
600/5
CTs
=
4.1
secondary
amperes
10’
=
-0.88
secondary
amperes
based
on
the
protected
line
CT ratio
of 600/5.
Note
the
negative
sign
because
I
flows
in
the
opposite
direction
in
the
parallel
line
(0
to
C)
from
that
in which
I
flows
in
the
protected
line
(A to
B).
9
=
790
Substituting
these
values
and
the
values
of impedance
assumed
above
into
equation
Tb
of
Appendix
I,
we
obtain:
K
Cos
(60-79)
F
(7.2
-2.4)(0.17)
(1.4)(-0.88)
+
(0.4
÷
0.17)
+
13.7
T =
0.204K
The
value
of T
could
be
obtained
for
all
three
basic
minimum
reach
settings.
However,
the
highest
one
should
be used.
For
the
three
ohm
basic
reach
settings
K
300.
Thus,
for
this
basic
tap
setting
the
restraint
tap
T should
be
no
larger
than:
T =
0.204K
=
61
percent
Consider
now
a
ground
fault
at
Fl
immediately
behind
the
relay.
Appendix H
indicates
the approach
to
calculate
the
maximum
safe
reach
setting
to eliminate
the
possibility
of
an
incorrect
operation
on
single
or
double
phase
to
ground
faults
at this
location.
Assume
that
a
system
study
yields
the
following
system
constants:
C
0.27
C 0
=
0.11
Z 1
=
0.875
secondary
ohms
=
1.05
/780
secondary
ohms
=
1.2
Using
the
3
ohm
basic
minimum
tap
settings
established
above
and
evaluating
equations
ha,
JIb
and
TIc
of
Appendix
II,
the
minimum
permissible
values
of
tap
setting
T
are
tabulated
below.
QUANTITY
VALUE
ZI
0.875
/82°
Z 0
1.05
/780
Z 0 /Z 1
1.2
Co
0.11
C
0.27
K
100
A
123°
8
82°
T
(Equation
ha)
-10.5 Percent
T
(Equation
JIb)
-18
Percent
T
(Equation
lIc)
-14.5
Percent
8

GEK-26423
Since
all
the
values
of
T
in
the
above table
are
negative,
these
equations
impose no
restrictions
on
the
tap
setting
for
this application.
Thus, the
relays
may
be
set
in
the
range of
10
to
61
percent.
Since the
61
percent
setting
will
insure that
the
relay
will reach
only
to the
remote
bus,
a lower
setting
should
be
used.
It
is
desirable
to
set
the
relay
to
reach
at
least
25
to
50
percent
beyond the
remote
terminal.
Thus,
for
50
percent additional
reach
the
restraint
tap
setting should
be:
61
T
=
41
percent
Set
tap
on
40
percent
These
same
calculations
should be
repeated
for
the
relays at
the
remote
end
of
the
line
at
terminal
B.
If
the
application
is
for
directional
comparison
carrier,
it
will
also
be
necessary
to
determine
the
set
tings
of the
carrier starting
CEYG51A
relays at
both
terminals.
The
carrier
start
relay
settings
should
be at
least
1.25
times
the
setting
of
the
tripping
relay at
the
remote
terminal.
This will
insure
that
the
carrier
starting
relay
at
the
rear
terminal
will
outreach
the
carrier
tripping
relay at
the
remote
terminal
and
they
will,
therefore,
coordinate
properly.
In
any
event
the
carrier
starting
units
should
be
set
as
sensitively
as
possible.
In
any
case,
ALWAYS
set
the
relays
that
must
coordinate
with
each
other
on
the
same
basic
minimum
tap
setting.
Thus,
the
carrier
start
CEYG51A relay
at
terminal B
should
be
set
with
the
same
basic
minimum
reach setting
as
the
tripping
CEYG51A
relay
at
terminal
A.
If zero
sequence
current
compensation
is
used, equation
Ic
should
be
used
instead
of
equation
lb.
Thus,
we
obtain.
6.95
- 2.36
4.59
K
=
= =
0.65
per
unit
3(2.36)
7.08
T
= 0.33K
=
0.33
x
300
=
99
percent
For
the
ground
fault F2
immediately
behind
the
relay,
use
the
equation
of
Appendix
III
to
calculate
the
maximum
safe
reach
setting
when
using
zero
sequence
current
compensation.
CONSTRUCTION
The Type
CEYG51A
relay
consists
of
three
inho—type,
4—pole
induction
cylinder
units.
Each
unit
has
an
associated
tapped
autotransformer
for
controlling
reach
and
adjustable
resistors
in
the
polarizing
and
restraint
circuits
for
adjustment
of
angle
and
basic minimum
ohmic
reach.
Figures
1
and
2
show
construc
tion
details
of
the
relay.
Internal
connections
of
the
relay
are
shown
in
Figure
3.
The
components
are
mounted
on
a
cradle
assembly
which can
be
easily
removed
from
the
relay
case.
The
cradle is
locked
in
the
case
by
means
of
latches
at
the
top
and
bottom.
The
electrical
connections
between
the
case
block
and
cradle
block
are
completed
through
a removable
connection
plug.
A
separate
testing
plug
can
be
inserted
in
place of
the
connection
plig
to
permit
testing
the
relay in
its
case.
The
cover
attaches
to
the case
from
the
front and
includes
the
target
reset
mechanism
and
an
interlock
arm
to
pre
vent
the
cover
from
being
replaced
until
the
connection
plug
has
been
inserted.
Outline
and
panel
drilling
dimensions
are
shown
in
Figure 15.
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
ststained
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.
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.
9

GEK-26423
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.
ViSUAL
INSPECTION
Check
the
nameplate
stamping
to
insure
that
the
model
number,
rating,
and
ohmic
range
of
the
relay
received
agree
with
the
requisition.
Remove
the
relay
from
its
case
and
check
by
visual
inspection
that
there
are
no
broken
or
cracked
molded
parts
or
other
signs
of
physical
damage,
and
that
all
screws
are
tight.
MECHANICAL
INSPECTION
It
is
recommended
that
the
following
mechanical
adjustments
be
checked:
1.
There
should
be
no
noticeable
friction
in
the
rotating
structure
of
each
unit.
The
normally
closed
contacts
should
be
closed
when
the
relay
is
in
the
upright
position.
2.
There
should
be
an
end
play
of
from
.005
to
.015
inches
on
the
shafts
of
the
rotating
structures.
The
lower jewel
screw
bearing
of
each
unit
should
be
screwed
firmly
in
place,
and
the
pivot
at
the
top
of
the
shaft
locked
by
its
set
screw.
3.
The
contact
gap
on
each
unit
should
be
approximately
.045
to
.065
inches.
There
should
be
.004
to
.012
inch
clearance
between
the
stationary
contact
rod
and
the
solid
backstop
when
the
contact is
open.
4.
The
spring
windup
should
be
sufficient
to
cause the
normally
closed
stationary
contact
to
deflect
so
that
it
just
touches
the
solid
stop
when
the
unit
is
dc—energized.
5.
The
clutch
of
each
unit
should
slip
when
a
force
of
45 to
65
grams
is
applied
to
the
moving
con
tact
assembly
at
the
moving
contact.
6.
The
armature
and
contacts
of
the
target
and
seal-in
unit
should
move
freely
when
operated
by
hand.
There
should
be
a
screw
in
only
one
of
the tap
positions
on
the
right
stationary
contact
strip.
Operate
the
armature
by
hand and
check
that
the
target
latches
in
its
exposed
position
before
the
contacts
close.
There
should
be
at
least
1/32
wipe
on
the
seal—in
contacts.
With
the
cover
fastened
securely
in
place,
check
that
the
target
resets positively
when
the
reset
button
at
the
5ottom
of
the
cover
is
operated.
7.
Check
the
location
of
the
contact
brushes
on
the
cradle
and
case blocks
against
the
internal
connection
diagram
for
the
relay.
Be
sure
that
the
shorting
bars
are
in
the
proper
locations
on
the
case
blocks,
and
that
the
long
and
short
brushes
on
the
cradle
block
agree
with
the
internal
connection
dia
gram.
Figure
11
shows
a
sectional
view
of
the
case
and
cradle
blocks with
the
connection
plug
in
place.
Note
that
there
is
an
auxiliary
brush
in each
position
on
the
case
block.
This
brush
should
be
formed
high
enough so
that
when
the
connecting
plug
is
inserted
it
engages
the
auxiliary
brush
before
striking
the
main
brush.
This
is
especially
important
in
current
and
other
circuits
with
shorting
bars
since
an
improper
adjustment
of
the
auxiliary
brush
could
result
in
a
CT
secondary
circuit
being momentarily
open
circuited.
ELECTRICAL
TESTS
It
is
recommended
that
the
following
electrical
checks
be
made
immediately
upon
receipt
of
the
relay.
1.
Polarity
Check
-
The
following
check
will
insure
that
the
relative
polarity
of
operating,
polarizing
and
restraint
circuits
of
each
unit
is
correct,
Each
unit
can
be
checked
individually
using
the
test
connections
in
Figure
9. With
all
tap leads
removed
the connections
shown
for
each
unit
should
CaUSe
the
contacts
of
that
unit
to
close.
With
the
E 2
tap
of
each
unit
set
in
the
80
percent
position,
that
unit
should
develop
a
strong
contact
opening
torque.
2.
Directional
Check
-
The
following
checks
are
to
determine
that
each
unit
has
correct
directional
characteristics.
Use
the
test
connections
shown
in
Figure
10.
Set the
voltages
to
two
volts
and
set
the
phase
shifter
so
that
the
current
leads
the voltage
by
30
degrees
with
the
connections
shown.
The
contacts
of
each
unit
should
close
at
some
value
less
than
the
minimum
amperes
given
in
Tble
III
and
remain
closed
as
the
current
is
increased
to
the
maximum
value
given
in
Table
III.
The
EL
taps
should
be
on 100
percent
for
these
tests.
10