ABB KLF Series Manual

Jill
II
ABIP
Instruction
Leaflet
I
.
L
.
41
-
748
N
ABB
Power
T
&
D
Company
Inc
.
Relay
Division
Coral
Springs
,
FL
33065
Type
KLF
Loss
-
of
-
Field
Relay
50
/
60
Hertz
Effective
February
1984
Supersedes
I
.
L
.
41
-
748
M
dated
April
1980
^
Denotes
change
since
previous
issue
CAUTION
:
Before
putting
protective
relays
into
service
,
make
sure
that
all
moving
parts
operate
freely
,
inspect
the
contacts
to
see
that
they
are
clean
and
close
properly
,
and
operate
the
relay
to
check
the
settings
and
electrical
connections
.
COMPENSATOR
The
compensators
which
are
designated
and
Tc
are
two
-
winding
air
gap
transformers
(
Fig
.
2
)
.
The
primary
or
current
winding
of
the
long
-
reach
compensator
T
^
\
has
seven
taps
which
ter
-
minate
at
the
tap
block
.
They
are
marked
2.4
,
3.16
,
4.35
,
5.93
,
8.3
,
11.5
,
15.8
.
The
primary
wind
-
ing
of
the
short
-
reach
compensator
T
^
also
has
seven
taps
which
terminate
at
this
tap
block
.
They
are
marked
0.0
,
0.91
,
1.27
,
1.82
,
2.55
,
3.64
,
5.1
.
A
voltage
is
induced
in
the
secondary
which
is
proportional
to
the
primary
tap
and
current
magnitude
.
This
proportionality
is
established
by
the
cross
sectional
area
of
the
laminated
steel
core
,
the
length
of
an
air
gap
which
is
located
in
the
center
of
the
coil
,
and
the
tightness
of
the
laminations
.
All
of
these
factors
which
influence
the
secondary
voltage
proportionality
have
been
precisely
set
at
the
factory
.
The
clamps
which
hold
the
laminations
should
not
be
disturbed
by
either
tightening
or
loosening
the
clamp
screws
.
APPLICATION
The
KLF
relay
is
a
single
-
phase
relay
con
-
nected
to
the
ac
side
of
a
synchronous
machine
and
contains
three
units
connected
so
that
the
operation
of
two
units
sounds
an
alarm
warning
the
operator
of
a
low
excitation
condition
,
and
the
additional
operation
of
the
third
sets
up
the
trip
circuit
.
The
relay
can
be
applied
without
modification
to
all
types
of
synchronous
ma
-
chines
,
such
as
turbo
-
generators
,
water
wheel
generators
or
synchronous
condensers
.
The
KLF
relay
is
designed
for
use
with
3
phase
3
wire
voltage
supply
and
may
use
wye
or
delta
-
connected
voltage
transformers
.
On
circuits
with
4
wire
wye
-
connected
voltage
transformers
,
the
type
KLF
-
1
relay
may
be
used
to
increase
security
dur
-
ing
inadvertent
loss
-
of
-
potential
(
such
as
due
to
a
blown
potential
fuse
)
.
The
secondary
winding
is
connected
in
series
with
the
relay
terminal
voltage
.
Thus
a
voltage
which
is
proportional
to
the
line
current
is
added
vectorially
to
the
relay
terminal
voltage
.
AUTO
-
TRANSFORMER
CONSTRUCTION
The
auto
-
transformer
has
three
taps
on
its
main
winding
,
S
,
which
are
numbered
1
,
2
,
and
3
on
the
tap
block
.
A
tertiary
winding
M
has
four
taps
which
may
be
connected
additively
or
sub
-
tractively
to
inversely
modify
the
setting
by
any
value
from
—
15
to
+
15
percent
in
steps
of
3
per
-
cent
.
The
relay
consists
of
two
-
air
gap
transformers
(
compensators
)
,
two
tapped
auto
-
transformers
,
one
reactor
,
one
cylinder
-
type
distance
unit
,
direc
-
tional
unit
with
adjustable
reactor
,
an
under
-
voltage
unit
with
adjustable
resistor
,
telephone
relay
,
and
an
ICS
indicating
contactor
switch
.
All
possible
contingencies
which
may
arise
during
installation
,
operation
,
or
maintenance
,
and
all
details
and
variations
of
this
equipment
do
not
purport
to
be
covered
by
these
instructions
.
If
further
information
is
desired
by
purchaser
regarding
this
particular
installation
,
operation
or
maintenance
of
this
equipment
,
the
local
Asea
Brown
Boveri
representative
should
be
contacted
.
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
Rear
View
Fig
.
1
.
Type
KLF
Relay
2
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
SECONDARY
PRIMARY
LAMINATED
CORE
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Sub
.
7
185
A
181
Sub
.
8
184
A
958
Fig
.
2
.
Compensator
Construction
Fig
.
3
.
Internal
Schematic
of
Type
KLF
Relay
in
FT
41
Case
The
sign
of
M
is
negative
when
the
R
lead
is
above the
L
lead
.
M
is
positive
when
L
is
in
a
tap
location
which is
above the
tap
location
of
the
R
lead
.
The
M
setting
is
determined
by
the
sum
of
per
unit
values between the
R
and
L
lead
.
The
ac
-
tual
per
unit
values
which
appear
on
the
tap
plate
between
taps
are
0
,
.
03
,
.
06
,
and
.
06
.
impedance
phasor
seen
by
the
relay
with
respect
to
its
characteristic
circle
.
Mechanically
,
the
cylinder
unit
is
composed
of
four
basic
components
:
A
die
-
cast
aluminum
frame
,
an
electromagnet
,
a
moving
element
assembly
,
and
a
molded
bridge
.
The
frame
serves
as
a
mounting
structure
for
the
magnetic
core
.
The
magnetic
core
which
houses
the
lower
pin
bearing
is
secured
to
the
frame
by
a
locking
nut
.
The
bearing
can
be
replaced
,
if
necessary
,
without
having
to
remove
the
magnetic
core
from
the
frame
.
The
auto
-
transformer
makes
it
possible
to
ex
-
pand
the basic
ranges
of
the
long
and
the
short
g
reach
compensators
by
a
multiplier
of
j
^
relay
ohm
setting
can
be
made within
+
1.5
per
-
cent
from
2.08
ohms
to
56
ohms
for
the long
reach
and
from
.
79
ohms
to
18
ohms
for
the
short
reach
.
-
.
Any
The electromagnet
has
two
sets
of
two
series
connected
coils
mounted
diametrically
opposite
one
another
to
excite
each
set
of
poles
.
Locating
pins
on
the
electromagnet
are
used
to
accurately
position
the
lower
pin
bearing
,
which is
mounted
on
the
frame
,
with
respect
to
the
upper
pin
bear
-
ing
,
which
is threaded
into the bridge
.
The elec
-
tromagnet
is
secured
to
the
frame
by
four
moun
-
ting
screws
.
IMPEDANCE
TRIPPING
UNIT
The
distance
unit
is
a
four
pole
induction
cylinder
type
unit
.
The
operating
torque
of
the
unit
is
proportional
to
the
produce
of
the
voltage
quantities
applied
to
the
unit
and
the sine
of
the
phase
angle
between the
applied
voltages
.
The
direction
of
the
torque
so
produced
depends
on
the
3
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
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DISTANCE
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GENERATOR
OUTPUT
91
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^
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DEVICE
NUMBER
CHART
GO
-
LOSS
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RELAY
.
TYPE
KIF
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DIRECTIONAl
UNIT
IN
TYPE
ILF
RELAY
ICS
-
INDICATING
CONTACTOR
SNITCH
IN
TYPE
ILF
RELAY
TA
-
LONG
REACH
COMPENSATOR
TC
-
SHORT
REACH
COMPENSATOR
V
-
VOLTAGE
UNIT
IN
TYPE
ILF
RELAY
X
-
TELEPNONE
RELAY
IN
TYPE
ILF
RELAY
Z
-
IMPEOANCE
UNIT
IN
TYPE
IlF
RELAY
43
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-
OFF
CUT
-
OUT
SNITCH
S
2
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P
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CIRCUIT
BREAIER
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BREAlER
AUXILIARY
SNITCH
1
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-
BREAXER
TRIP
COIL
f
-
Jf
MA
+
CONTACT
/
CLOSES
*
-
FUSE
ILF
RELAY
SEPARATELY
FROM
ALL
OTHER
SECONDARY
BURDENS
•
'
'
BC
(
«
£
P
>
POLARIZING
COILS
—
OPERATING
COILS
43
SNITCH
(
OPTIONAL
)
-
IA
1
CONTACTS
OFF
ALAIN
*
TRIP
\
1
-
2
X
X
3
-
4
X
DIRECTIONAL
UNIT
VECTORS
FOR
1001
P
.
F
.
GENERATOR
OUTPUT
X
-
OENOTES
CONTACTS
CLOSED
Sub
.
10
290
B
607
Fig
.
4
.
External
Schematic
of
Type
KLF
Relay
tromagnet
and
the
magnetic
core
.
The
stops
are
an
integral
part
of
the
bridge
.
The
moving
element
assembly
consists
of
a
spiral
spring
,
contact
carrying
member
,
and
an
aluminum
cylinder
assembled
to
a
molded
hub
which
holds
the
shaft
.
The
hub
to
which
the
moving
-
contact
arm
is
clamped
has
a
wedge
-
and
-
cam
construction
,
to
provide
low
-
bounce
contact
action
.
A
casual
inspection
of
the
assembly
might
lead
one
to
think
that
the
contact
arm
bracket
does
not
clamp
on
the
hub
as
tightly
as
it
should
.
However
,
this
adjustment
is
accurately
made
at
the
factory
and
is
locked
in
place
with
a
lock
nut
and
should
not
be
changed
.
Optimum
contact
ac
-
tion
is
obtained
when
a
force
of
4
to
10
grams
pressure
applied
to
the
face
of
the
moving
contact
will
make
the
arm
slip
from
the
condition
of
reset
to
the
point
where
the
clamp
projection
begins
to
ride
up
on
the
wedge
.
The
free
travel
can
vary
between
15
°
to
20
°
.
The
bridge
is
secured
to
the
electromagnet
and
frame
by
two
mounting
screws
.
In
addition
to
holding
the
upper
pin
bearing
,
the
bridge
is
used
for
mounting
the
adjustable
stationary
contact
housing
.
This
stationary
contact
has
.
002
to
.
006
inch
follow
which
is
set
at
the
factory
by
means
of
the
adjusting
screw
.
After
the
adjustment
is
made
the
screw
is
sealed
in
position
with
a
material
which
flows
around
the
threads
and
then
solidifies
.
The
stationary
contact
housing
is
held
in
position
by
a
spring
type
clamp
.
The
spring
adjuster
is
located
on
the
underside
of
the
bridge
and
is
at
-
tached
to
the
moving
contact
arm
by
a
spiral
spr
-
ing
.
The
spring
adjuster
Is
also
held
in
place
by
a
spring
type
clamp
.
When
contacts
close
,
the
electrical
connection
is
made
through
the
stationary
contact
housing
clamp
,
to
the
moving
contact
,
through
the
spiral
spring
and
out
to
the
spring
adjuster
clamp
.
The
shaft
has
removable
top
and
bottom
jewel
bearings
.
The
shaft
rides
between
the
bottom
pin
bearing
and
the
upper
pin
bearing
with
the
cylinder
rotating
in
an
air
gap
formed
by
the
elec
-
4
Courtesy of NationalSwitchgear.com

l
.
L
.
41
-
748
N
v P
0
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)
=
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*
vAT
+
X
+
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+
X
a
)
JA
»
o
zc
-
zC
CONTACT
CLOSES
V
0
P
*
=
VAT
-
R
+
R
-
R
+
R
-
R
+
R
7
ZA
>
ZA
vPOL
(
«
Efr
-
'
)
-
*
(
-
l
.
5
IAZC
)
,
1
-
X
-
X
(
Q
)
WITH
ZC
«
0
(
b
)
WITH
Zc
>
0
(
C
)
WITH
ZC
<
0
b
)
IAHIJI
±
1
£
°
b
.
I
<
IKVAT
CONTACT
CLOSES
Sub
.
2
185
A
182
VOP VAT
I
1
Fig
.
5
.
R
-
X
Diagram
Characteristics
with
Various
Zc
—
Compensator
Settings
+
l
.
5
IaZA
I
DIRECTIONAL
UNIT
The
directional
unit is
an
induction
cylinder
unit
operating
on
the
interaction
between
the
polarizing
circuit flux
and the
operating
circuit
flux
.
CONTACT
CLOSES
^
K
(
-
I
.
SIAZC
)
vlT
vOP
C
)
I A
=
|
IAILL
9 0
°
I J
H
-
1.5
IAZA
v
POL
(
REF
)
Sub
.
2
185
A
331
Mechanically
,
the
directional
unit is
composed
of
the
same
basic
components
as
the distance
unit
:
A
die
-
cast
aluminum
frame
,
an
electromagnet
,
a
moving
element
assembly
,
and
a
molded
bridge
.
The
electromagnet
has
two
series
-
connected
polarizing
coils mounted
diametrically
opposite
one
another
;
two
series
-
connected
operating
coils
mounted
diametrically
opposite
one
another
;
two
magnetic
adjusting
plugs
;
upper
and
lower
ad
-
justing
plug
clips
,
and
two
locating
pins
.
The
locating
pins
are
used
to
accurately
position
the
lower
pin
bearing
,
which is
threaded
into
the
bridge
.
The
electromagnet
is secured
to
the
frame
by
four
mounting
screws
.
Fig
.
6
.
Effect
of
Compensator
Voltages
(
Zc
is
positive
)
holding
the
upper
pin
bearing
,
the
bridge is
used
for
mounting
the
adjustable
stationary
contact
housing
.
The
stationary
contact
housing
is held
in
position
by
a
spring
type
clamp
.
The spring
ad
-
juster
is
located
on
the
underside
of
the
bridge
and
is
attached
to
the
moving
contact
arm
by
a
spiral
spring
.
The
spring
adjuster
is
also
held
in
place
by
a
spring
type
clamp
.
UNDERVOLTAGE
UNIT
The
voltage
unit is
an
induction
-
cylinder
unit
.
Mechanically
,
the
voltage
unit
is
composed
like
the
directional unit
,
of four
components
:
A
diecase
aluminum
frame
,
an
electromagnet
,
a
moving
element
assembly
,
and
a
molded
bridge
.
The
electromagnet
has
two
pairs
of
voltage
coils
.
Each
pair
of
diametrically
opposed
coils
is
connected
in
series
.
In
addition
one
pair
is
in
series
with
an
adjustable
resistor
.
These
sets
are
in
parallel
as
shown
in
Fig
.
3
.
The
adjustable
resistor
serves
not
only
to
shift
the
phase
angle
of
the
one
The
moving
element
assembly
consists
of
a
spiral
spring
,
contact
carrying
member
,
and
an
aluminum
cylinder
assembled
to
a
molded
hub
which
holds the
shaft
.
The
shaft
has
removable
top
and
bottom
jewel
bearings
.
The
shaft
rides
between
the
bottom
pin
bearing
and the
upper
pin
bearing
with
the
cylinder
rotating
in
an
air
gap
formed
by
the
electromagnet
and
the
magnetic
core
.
The
bridge is secured
to
the
electromagnet
and
frame
by
two
mounting
screws
.
In
addition
to
5
Courtesy of NationalSwitchgear.com

I
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Fig
.
7
.
Typical
Machine
Capacity
Curves
Plotted
on
a
Per
Unit
KVA
Basis
(
183
,
500
KVA
,
45
#
H
2
,
18
KV
,
0.9
pt
,
0.64
SCR
,
inner
-
cooled
,
3600
rpm
.
)
flux
with
respect
to
the
other
to
produce
torque
,
but
it
also
provides
a
pick
-
up
adjustment
.
Otherwise
the
undervoltage
unit is similar
in
its
construction
to
the
directional unit
.
TELEPHONE
RELAY
The
telephone
relay
(
X
)
has
a
slow
drop
-
out
characteristic
.
When
energized
,
the
solenoid
core
attracts
an
iron
right
-
angle
armature
bracket
which
in
turn
opens
the
break
contacts
.
In
actual
service
,
the
relay
is
normally
energized holding
the
break
contacts
open
.
(
Note
:
the
make
contacts
are
not
used
.
)
Drop
-
out
delay
adjustment
is obtained
by
varying
the
air
-
gap
between
the
armature
and
the
core
.
INDICATING
CONTACTOR
SWITCH
UNIT
(
ICS
)
Fig
.
8
.
Typical
Machine
Capacity
Curves
and
Sample
KLF
Settings
—
Per
Unit
impedance
The
front
spring
,
in
addition
to
holding the
target
,
provides
restraint
for
the
armature
and
thus controls
the
pickup
of
the
switch
.
OPERATION
The
relay
is
connected
and
applied
to
the
system
as
shown
in
Fig
.
4
.
The
directional unit
closes
its
contacts
for
lagging
var
flow into
the
machine
.
Its
zero
torque
line
has been
set
at
—
13
°
from
the
R
-
axis
.
Its
primary
function
is
to
prevent
operation
of
the
relay
during
external
faults
.
The
impedance
unit
closes its
contacts
when
,
as
a
result
of
reduction
in
excitation
,
the
impedance
of
the
machine
as
viewed
from
its
terminals
is
less
than
a
predetermined
value
.
The
operation
of
both
the
impedance
and
directional
units
sounds
an
alarm
,
and
the
additional
operation
of
the under
-
voltage
unit
trips
the
machine
.
As
shown
in
Fig
.
4
,
the
contacts
of
all
three units
are
connected
in
series
across
a
telephone
type
relay
designated
X
,
which
provides
approximately
15
cycles
time
The dc
indicating
contactor
switch is
a
small
clapper
-
type
device
.
A
magnetic
armature
,
to
which leaf
-
spring
mounted
contacts
are
attached
,
is
attracted
to
the
magnetic
core
upon
energiza
-
tion
of
the
switch
.
When
the switch
closes
,
the
moving
contacts
bridge
two
stationary
contacts
,
completing
the
trip
circuit
.
Also
during
this
opera
-
tion
two
fingers
on
the
armature
deflect
a
spring
located
on
the
front of
the
switch
,
which
allows
the
operation
indicator
target
to
drop
.
The
target
is
reset
from
the
outside
of
the
case
by
a
push
rod
located
at
the
bottom
of
the
cover
.
6
Courtesy of NationalSwitchgear.com

I
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delay
on
dropout
before
energizing
the
trip
coil
.
This
time
delay
is
to
insure
positive
contact
coor
-
dination
under
all
possible
operating
conditions
.
During
normal
conditions
,
all
contacts
are
open
.
position
(
+
ZQ
)
the
circle
includes
the
origin
;
with
the
opposite
link
position
(
—
ZQ
)
the
circle
misses
the
origin
.
The
following
paragraphs
explain
this
compensator
action
.
PRINCIPLE
OF
DISTANCE
UNIT
OPERATION
The
distance
unit
is
an
inducation
cylinder
unit
having
directional
characteristics
.
Operation
depends
on
the
phase
relationship
between
magnetic
fluxes
in
the
poles
of
the
electromagnet
.
Referring
to
Fig
.
4
note
that
Rg
and
Cg
cause
the
polarizing
voltage
to
be
shifted
90
°
in
the
lead
-
ing
direction
.
Thus
,
when
the
current
is
zero
,
polar
-
ing
voltage
VpQL
leads
the
operating
voltage
VQP
by
90
°
,
as
shown
in
Fig
.
6
(
a
)
.
This
relation
produces
restraining
torque
.
To
illustrate
how
Z
\
fixesd
the
long
reach
,
assume
a
relay
current
which
leads
VJN
by
90
°
and
of
sufficient
magnitude
to
operate
the
relay
.
This
means
the
apparent
im
-
pedance
is
along
the
—
X
axis
.
Note
in
Fig
.
6
(
b
)
that
the
Z
/
±
compensation
reverses
the
operating
voltage
phase
position
.
The
relay
balances
when
this
voltage
is
zero
.
Note
that
this
balance
is
un
-
affected
by
the
ZQ
compensation
,
since
this
com
-
pensation
merely
increases
the
size
of
VpQL
-
One
set
of
opposite
poles
,
designated
as
the
operating
poles
are
energized
by
voltage
Vjy
modi
-
fied
by
a
voltage
derived
from
the
long
reach
com
-
pensator
T
^
.
The
other
set
of
poles
(
polarizing
)
are
energized
by
the
same
voltage
Vj
-
p
except
modified
by
a
voltage
derived
from
the
short
reach
compensator
TQ
The
flux
in
the
polarizing
pole
is
so
adjusted
that
the
unit
closes
its
contacts
when
-
ever
flux
in
the
operating
set
of
poles
leads
the
flux
in
the
polarizing
set
.
For
lagging
current
conditions
note
in
Fig
.
6
(
c
)
how
VpQL
is
reversed
by
the
ZQ
compensa
-
tion
.
In
this
case
the
Z
\
compensation
has
no
effect
on
the
balance
point
.
This
explains
why
the
reach
point
is
fixed
independently
by
ZQ
.
The
voltage
Vjy
is
equal
to
V
IT
=
V
12
+
0.5
V
23
=
1.5
V
1
N
(
1
)
As
shown
in
Fig
.
4
,
one
-
half
of
V
23
,
voltage
is
physically
derived
in
the
relay
at
midtap
of
a
re
-
actor
connected
across
voltage
V
23
.
Reach
of
the
distance
unit
is
determined
by
compensators
T
^
and
T
^
as
modified
by
auto
-
transformer
settings
.
Compensators
T
^
and
T
^
are
designed
so
that
its
mutual
impedance
Z
\
or
ZQ
has
under
CHARACTERISTICS
and
SET
-
TINGS
.
The
mutual
impedance
of
a
compensator
is
defined
here
as
the
ratio
of
secondary
induced
voltage
to
primary
current
and
is
equal
to
T
.
Each
secondary
compensator
voltage
is
in
series
with
the
voltage
Vjy
.
Compensator
voltages
is
in
series
with
the
voltage
V
jp
.
Compensator
voltages
are
equal
to
1.5
Ij
Z
\
for
long
reach
compensator
and
1.5
11
ZQ
for
short
reach
compensator
,
where
I
,
is
the
relay
current
.
Fig
.
5
shows
how
the
compensation
voltages
1.5
11
Z
\
and
1.5
I
j
ZQ
influence
the
R
-
X
circle
.
Note
that
Z
\
independently
determines
the
“
long
reach
”
,
while
ZQ
independently
fixes
the
“
short
reach
”
.
With
the
reversing
links
in
the
normal
Fig
.
6
assumes
that
ZQ
is
positive
(
circle
in
-
cludes
origin
)
.
If
the
current
coil
link
is
reversed
,
the
compensation
becomes
+
1.51
,
ZQ
.
In
Fig
.
6
(
b
)
this
change
would
result
in
,
VpQL
being
reduced
rather
increased
by
the
compensation
.
As
the
current
increases
VpQL
will
finally
be
reversed
,
reestablishing
restraining
torque
.
Thus
,
the
current
need
not
reverse
in
order
to
obtain
a
“
short
reach
”
balance
point
.
Instead
the
apparent
impedance
need
only
move
towards
the
origin
in
the
-
X
region
to
find
the
balance
point
.
Therefore
,
the
circle
does
not
include
the
origin
with
a
reversed
link
position
.
CHARACTERISTICS
The
type
KLF
relay
is
available
in
one
range
.
DISTANCE
UNIT
The
distance
unit
can
be
set
to
have
characteristic
circles
that
pass
through
origin
,
in
-
clude
it
,
or
exclude
it
,
as
shown
in
Fig
.
5
.
7
Courtesy of NationalSwitchgear.com

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To
change
taps
requires
connecting
the
lead
located
in
front
of
the
tap
block
to
the
desired
set
-
ting
by
means
of
a
screw
connection
.
TRIP
CIRCUIT
CONSTANT
Indicating
Contactor
Switch
(
ICS
)
0.2
ampere
tap
-
6.5
ohm
dc
resistance
2.0
ampere
tap
-
0.15
ohm
dc
resistance
The
ZA
and
ZQ
values
are
deternrned
by
com
-
pensator
settings
and
modified
by
autotransformer
settings
S
,
L
,
and
R
.
The
impedance
settings
in
ohms
reach
can
be
made
for
any
value
from
2.08
to
56
ohms
for
ZA
,
and
from
0.79
ohm
to
18
ohms
for
ZQ
in
steps
of
3
percent
.
The
taps
are
marked
as
follows
:
BURDEN
TA
Current
at
5
Amps
2.4
,
3.16
,
4.35
,
5.93
,
8.3
,
11.5
,
15.8
TA
&
TC
Settings
VA
Angle
of
Lag
60
Hz
50
Hz
60
Hz
50
Hz
TC
0.0
,
0.91
,
1.27
,
1.82
,
2.55
,
3.64
,
5.1
77
°
74
°
18.6
Max
.
Min
.
15.7
51
°
46
°
3.4
3.8
(
SA
.
sC
)
Potential
at
120
Volts
Phase
AB
1
,
2
,
3
,
(
MA
,
MC
)
VA
Angle
of
Lag
60
Hz
50
Hz
+
values
between
taps
.
03
,
.
06
,
.
06
SA
=
sc
60
Hz
50
Hz
2
°
2
°
1
18.0
18.0
DIRECTIONAL
UNIT
The
KLF
relay
is
designed
for
potential
polarization
with
an
internal
phase
shifter
,
so
that
maximum
torque
occurs
when
the
operating
current
leads
the
polarizing
voltage
by
ap
-
proximately
13
degrees
.
The
minimum
pickup
has
been
set
by
the
spring
tension
to
be
approximately
1
volt
and
5
amperes
at
maximum
torque
angle
.
31
°
26
°
2
14.4
13.8
39
°
34
°
3
13.9
13.0
Phase
BC
VA
Angle
of
Lag
60
Hz
50
Hz
SA
=
SC
60
Hz
50
Hz
12
°
10
°
1
2.6
2.6
38
°
33
°
2
5.9
5.5
42
°
37
°
3
6.6
6.1
UNDERVOLTAGE
UNIT
The
undervoltage
unit
is
designed
to
close
its
contacts
when
the
voltage
is
lower
than
the
set
value
.
The
undervoltage
unit
is
energized
with
Vjj
-
voltage
.
This
voltage
is
equal
to
1.5
V
^
q
voltage
.
The
contacts
can
be
adjusted
to
close
over
the
range
of
65
to
85
percent
of
normal
system
voltage
.
The
dropout
ratio
of
the
unit
is
98
percent
or
higher
.
D
-
C
Circuit
Watts
+
Rated
Rating
125
3.9
250
7.8
THERMAL
RATINGS
Potential
:
132
volts
(
L
-
L
)
continuous
Current
:
8
amperes
continuous
200
amperes
for
1
second
TRIP
CIRCUIT
The
main
contacts
will
safely
close
30
amperes
at
250
volts
dc
and
the
seal
-
in
contacts
of
the
in
-
dicating
contactor
switch
will
safely
carry
this
current
long
enough
to
trip
a
circuit
breaker
.
SETTING
CALCULATIONS
GENERAL
SETTING
RECOMMENDATIONS
The
KLF
relay
may
be
applied
as
a
single
-
zone
device
,
or
two
relays
may
be
used
to
provide
two
-
zone
protection
.
The
single
-
zone
setting
may
be
fully
offset
(
Zone
-
1
)
or
may
include
the
origin
The
indicating
contactor
switch
has
two
taps
that
provide
a
pick
-
up
setting
of
0.2
or
2
amperes
.
8
Courtesy of NationalSwitchgear.com

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TABLEI
RECOMMENDED
SETTINGS
FOR
KLF
RELAY
ZONE
1
(
ALONE
)
ZONE
2
(
ALONE
)
BOTH
ZONE
1
&
ZONE
2
See
Fig
.
10
IMPEDANCE
SETTING
See
Fig
.
11
See
Figs
.
10
&
11
VOLTAGE
SETTING
(
a
)
Contact
shorted
or
(
b
)
Set
at
80
%
for
security
80
%
Zone
1
voltage
contact
shorted
with
Zone
2
set
at
80
%
TD
-
1
Zone
1
timer
=
VA
sec
Zone
2
timer
=
1
sec
VA
to
1
sec
(
1
sec
preferred
)
VA
to
1
sec
(
1
sec
preferred
)
Not
required
for
(
a
)
above
.
For
(
b
)
above
use
1
min
.
TD
-
2
1
min
.
1
min
.
Less
sensitive
to
stable
system
swings
ADVANTAGES
1
)
More
sensitive
to
LOF
condition
2
)
Can
operate
on
partial
LOF
3
)
Provide
alarm
features
for
manual
operation
(
1
)
Same
as
(
1
)
,
(
2
)
and
(
3
)
at
left
.
(
2
)
Provides
back
-
up
protection
TABLE
II
SPECIAL
SETTINGS
FOR
MULTI
MACHINES
BUSSED
AT
MACHINE
TERMINALS
ZONE
1
(
ALONE
)
ZONE
2
(
ALONE
)
BOTH
ZONE
1
&
ZONE
2
See
Fig
.
10
IMPEDANCE
SETTING
See
Fig
.
11
See
Figs
.
10
&
11
VOLTAGE
SETTING
(
a
)
Contact
shorted
or
(
b
)
set
at
87
%
for
security
87
%
Zone
l
voltage
contact
shorted
with
Zone
2
set
at
87
%
TD
-
l
Zone
l
timer
=
VA
sec
Zone
2
timer
=
l
sec
VA
to
1
sec
(
1
sec
preferred
)
VA
to
1
sec
(
1
sec
preferred
)
TD
-
2
Not
required
for
(
a
)
above
(
a
)
above
.
For
(
b
)
above
use
10
sec
for
cond
.
cooled
,
25
sec
for
conv
.
cooled
10
sec
for
cond
.
cooled
.
25
sec
for
conv
.
cooled
.
10
sec
for
cond
.
cooled
25
sec
for
conv
.
cooled
9
Courtesy of NationalSwitchgear.com

I
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N
Converting
to
the
impedance
curve :
lvt
2
|
=
102
(
KVA
)
c
0.715
=
1.4
per
unit
(
Zone
-
2
)
.
The
two
-
zone
application
would
require
a
zone
-
1
KLF
and
a
zone
-
2
KLF
,
approximately
equivalent
to two
-
zone
step
-
distance
line
protec
-
tion
.
A
generalized
external
schematic
,
which is
applicable
to
either
Zone
-
1
or
Zone
-
2
relays
is
shown
in
Fig
.
9
.
The
recommended
settings
and
relative
advantages
of
these various
con
-
figurations
are
summarized
in
Table
I
.
!
z
|
=
Since
the
angle
remains the
same
,
the
im
-
pedance plot
conversion
is
:
Z
=
1.4
/
—
33.6
°
,
as
shown
in
Fig
.
8
.
The
single
-
zone
and
two
-
zone
setting
recommendations
are
modified
when
two
or
more
machines
are
bussed
at
the machine
terminals
.
The
voltage
and time
delay
considerations
are
treated
in
detail
in
other
sections
of
this
leaflet
.
The
recommended
settings
are
outlined
in
Table
After
plotting
the
steady
-
state
stability
limit
and
the
machine
capability
curves
on
the
R
-
X
dia
-
gram
,
plot
the
relay
circle
between
the
stability
limit
and the
capability
curve
.
(
Note
in
Fig
.
8
that
the
relay
circle
cannot
be
plotted
within
the
60
#
—
Vj
=
0.95
curve
,
since
the
machine
is
beyond
the
steady
-
state
stability
limit
for
these
conditions
.
)
This
plot
defines
the
desired reach
Z
\
and
radius
R
of
the
relay
circle
.
Then
use
the
following
pro
-
cedure
to
select
tap
settings
.
1000
(
kv
)
2
Rc
II
.
ZONE
-
2
SETTING
CALCULATIONS
(
DISTANCE
UNIT
)
Set
the
distance
unit
to
operate
before
the
steady
-
state
stability
limit
is exceeded
.
Also
,
to
allow maximum
output
without
an
alarm
,
set
the
distance unit
to
allow
the
machine
to
operate
at
maximum
hydrogen
pressure
and
0.95
per
unit
voltage
(
lowest
voltage
for
which the
capability
curve
machine
cannot
be
realized
without
ex
-
ceeding
the
steady
-
state
stability
limit
,
set
the
dis
-
tance
unit
to
operate
before
the
steady
-
state
limit
is
exceeded
.
Capability
curves
similar
to
Fig
.
7
are
obtained
from
the
generator
manufacturer
.
(
2
)
ohms
zbase
-
(
kva
)
Ry
where
Zbase
=
one
Per
un
^
primary
ohms
/
as
seen
from
the
relay
kv
=
rated
phase
-
to
-
phase
voltage
of
the
machine
.
kva
=
rated kva
of
the machine
Rc
=
the
current
transformer
ratio
.
Rv
=
the
potential
transformer
ratio
.
To
determine
the
desired
setting
convert
the
capability
curve
of
Fig
.
7
of
the
impedance
curve
VT
2
|
(
KVA
)
C
per
wire
terminal
voltage
and
(
KVA
)
c
is the
per
unit
output
.
The
angle
of
each
point
on
the
im
-
pedance
curve
is
the
same
angle
as
the
corres
-
ponding
point
on
the
capability
curve
.
of
Fig
.
8
by
calculating
-
,
where
Vj
is
the
The
actual
settings
,
and
ZQ
,
are
:
ZA
=
(
ZA
Per
unit
)
x
(
zbase
)
(
3
)
ZC
=
(
zc
Per
unit
)
x
(
zbase
)
=
(
4
)
(
2
R
—
Z
^
)
x
(
Zbase
)
For
example
,
from
Fig
.
7
,
an
output
of
0.6
per
unit
KW
on
30
#
hydrogen
pressure
curve
is
—
0.4
per
unit reactive
KVA
.
Therefore
,
Where
R
=
radius
of
circle
in
per
unit
.
The
tap
-
plate
settings
are
made
accord
-
ing
to
equations
:
(
KVA
)
c
=
V
(
0
-
6
)
2
+
(
_
o
.
4
)
2
=
0.715
per
unit
and
,
9
=
Tan
—
1
(
TS
(
5
)
-
0.4
ZA
(
°
r
ZC
)
=
)
=
-
33.6
°
1
+
M
0.6
10
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
(
2
)
ZA
=
ZA
(
per
unit
)
Zbase
=
(
1
-
68
(
16.45
)
=
27.6
ohms
(
3
)
Zc
=
Zc
(
per
unit
)(
ZbaSe
)
=
(
°
-
20
)
(
16.45
)
=
3.29
ohms
To
set
=
27.6
Step
1
:
The
lowest
tap
SA
for
18.6
SA
greater
than
ZA
=
27.6
is
2
.
Set
SA
in
tap
2
.
Step
2
:
TA
nearest
to
27.6
=
13.8
is
TA
=
15.8
where
:
T
=
compensator
tap
value
.
S
=
auto
-
transformer
primary
tap
value
.
M
=
auto
-
transformer
secondary
tap
value
.
(
M
is
a
per
-
unit
value
determined
by
taking
the
sum
of
the
values
between
the
L
and
the
R
leads
.
The
sign
is
positive
when
L
is
above
R
and
acts
to
lower
the
Z
setting
.
The
sign
is
negative
when
R
is
above
L
and
acts
to
raise
the
Z
setting
)
.
The
following
procedure
should
be
followed
to
obtain
an
optimum
setting
of
the
relay
:
1
.
Select
the
lowest
tap
S
which
give
a
product
of
18.6
SA
greater
than
desired
ZA
and
a
product
of
6
Sc
greater
than
desired
ZQ
.
2
.
Select
a
value
of
M
that
will
most
nearly
make
it
equal
to
:
2
Set
TA
in
15.8
tap
15.8
x
2
M
TASA
Step
3
:
MA
=
1.145
-
1
=
+
.
145
Set
M
=
+
.
15
.
Place
R
lead
in
0
,
L
lead
in
upper
.
06
.
The
relay
setting
is
now
:
TASA
=
15.8
x
2
_
31.6
1
+
M
1
+
0.15
1.15
27.6
Actual
ZA
=
=
27.5
TS
This
is
99.7
%
of
the
desired
setting
.
To
set
ZQ
=
3.29
ohms
:
Step
1
:
The
lowest
tap
S
^
for
6
SQ
greater
than
3.29
is
Sc
=
1
.
Set
Sc
=
1
Step
2
:
Tc
nearest
to
3.29
=
3.29
is
3.64
M
=
1
.
Z
If
the
sign
is
negative
,
then
the
M
taps
are
con
-
nected
with
the
R
lead
above
the
L
lead
to
raise
the
setting
.
SAMPLE
CALCULATIONS
Assume
that
a
KLF
relay
is
to
be
applied
to
the
following
machine
:
3
-
phase
,
60
hertz
,
3600
rpm
,
18
kv
,
rated
at
0.9
pf
,
183
,
500
KVA
at
45
#
H
2
.
Rc
=
1400
/
1
If
the
recommended
setting
from
Fig
.
8
is
used
:
ZA
per
unit
=
1.68
1
Set
Tc
in
3.64
tap
.
TCSC
3.64
x
1
Rv
=
150
/
1
Step
3
:
Me
=
1
=
-
1
=
1.107
3.29
ZC
-
1
=
+
.
107
Hence
,
the
nearest
values
is
+
.
12
.
Now
set
R
lead
in
0.03
tap
and
L
lead
in
the
upper
.
06
tap
.
(
Since
Me
has
plus
signn
lead
L
must
be
over
ZQ
per
unit
=
2
R
—
ZA
=
2
x
0.94
-
1.68
=
0.20
(
The
relay
circle
in
Fig
.
8
was
obtained
by
trial
and
error
using
a
compass
to
get
the
desired
ra
-
dius
and
offset
.
)
R
.
)
TCSC
1000
(
kv
)
2
RC
_
1000
x
(
18
)
2
x
1400
(
kva
)
Rv
3.64
x
1
Then
,
ZQ
==
3.25
(
1
)
Zbase
-
(
1
+
Mc
)
1
+
-
12
ohms
,
or
98.8
%
of
the
desired
value
.
183
,
500
x
150
16.45
ohms
11
Courtesy of NationalSwitchgear.com

I
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L
.
41
-
748
N
UNDERVOLTAGE
UNIT
A
.
The
undervoltage
unit
is
usually
set
to
a
value
corresponding
to
the
minimum
safe
system
voltage
for
stability
.
This
voltage
depends
on
many
factors
,
but
is
usually
between
70
and
80
percent
of
normal
system
voltage
.
The
under
-
voltage
unit
is
set
at
the
factory
for
77
%
of
nor
-
mal
system
voltage
,
or
92
VJ
^
.
L
(
equivalent
to
80
volts
on
the
undervoltage
unit
)
.
In
cases
where
each
generator
is
equipped
with
its
own
transformer
(
unit
connected
system
)
the
stan
-
dard
factory
setting
is
usually
satisfactory
for
the
undervoltage
unit
.
B
.
In
applications
where
multiple
units
are
con
-
nected
to
the
same
bus
,
loss
of
field
of
one
unit
may
not
depress
the
bus
voltage
to
the
point
where
the
undervoltage
unit
will
operate
if
it
has
the
standard
setting
.
The
following
recom
-
mendations
should
be
considered
:
1
.
For
cross
-
compound
turbine
generator
ap
-
plications
,
the
dropout
voltage
(
i
.
e
.
,
the
voltage
at
which
the
back
contact
of
the
undervoltage
unit
closes
)
of
the
under
-
voltage
unit
should
be
set
for
87
%
of
normal
voltage
(
equivalent
to
90
volts
on
the
under
-
voltage
unit
)
.
2
.
For
waterwheel
generator
applications
,
with
multiple
machine
tied
to
a
common
bus
,
the
dropout
voltage
of
the
undervoltage
unit
should
be
set
at
87
%
.
3
.
For
all
applications
where
the
alarm
func
-
tion
is
not
to
be
used
the
undervoltage
unit
contact
should
be
jumped
(
shorted
)
.
4
.
For
industrial
applications
,
with
two
or
more
generators
on
the
same
bus
,
the
under
-
voltage
unit
contact
should
be
jumped
(
shorted
)
and
the
alarm
circuit
not
used
.
5
.
For
small
Synchronous
condenser
and
large
motor
applications
,
the
undervoltage
unit
contact
should
,
in
general
,
be
jumped
(
short
-
ed
)
,
and
the
alarm
circuit
not
used
.
In
special
cases
the
machine
may
be
treated
as
in
2
,
above
,
where
knowledge
exists
of
expected
undervoltage
level
.
6
.
For
gas
turbine
units
,
with
high
generator
impedance
,
the
undervoltage
unit
may
not
operate
.
For
these
applications
the
under
-
voltage
contacts
should
be
short
circuited
.
C
.
The
desired
undervoltage
unit
setting
is
com
-
puted
by
:
Setting
=
Vjy
=
1.5
Vjjq
where
Vjjq
is
phase
-
to
-
neutral
voltage
.
Note
:
An
electrical
check
of
this
particular
setting
is
outlined
in
this
instruction
leaflet
,
under
the
heading
“
Acceptance
Check
”
.
TIME
DELAY
CONSIDERATIONS
It
may
be
conservatively
stated
that
the
rotor
structure
and
stator
heating
,
as
a
result
of
a
shorted
field
can
be
tolerated
for
10
seconds
on
a
conductor
-
cooled
machine
and
25
seconds
for
a
conventional
machine
.
This
time
may
be
as
low
as
5
seconds
for
an
open
field
(
as
opposed
to
a
field
closed
through
a
field
discharge
resistor
or
an
ex
-
citer
armature
)
and
as
high
as
one
minute
where
the
concern
is
protection
of
an
adjacent
tandem
compound
unit
against
partial
loss
-
of
-
excitation
in
the
faulted
machine
.
In
view
of
the
above
considerations
,
it
is
often
desirable
to
use
an
external
timer
in
conjunction
with
the
KLF
Relay
.
The
following
examples
are
applications
where
an
external
timer
would
be
desirable
:
1
.
Cross
-
compound
units
,
with
undervoltage
unit
setting
of
90
volts
,
should
use
an
ex
-
ternal
timer
to
assure
tripping
before
ther
-
mal
damage
can
result
.
The
timer
is
ener
-
gized
at
the
alarm
output
and
should
be
set
for
10
seconds
for
a
cross
-
compound
con
-
ductor
cooled
machine
.
For
a
conventionally
cooled
cross
-
compound
machine
,
the
ex
-
ternal
timer
should
be
set
for
25
seconds
.
As
an
alternative
to
this
,
the
KLF
with
shorted
undervoltage
contacts
may
be
ap
-
plied
and
the
alarm
feature
not
used
.
With
this
arrangement
,
tripping
takes
place
after
the
250
ms
time
delay
provided
by
the
X
unit
in
KLF
relay
.
2
.
Machines
connected
to
a
common
high
voltage
bus
may
be
protected
against
loss
of
voltage
due
to
loss
-
of
-
excitation
in
an
adjacent
machine
by
using
a
one
minute
timer
driven
by
the
alarm
output
of
the
loss
-
of
-
field
relay
.
12
Courtesy of NationalSwitchgear.com

I
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L
.
41
-
748
N
3
.
In
some
critical
applications
2
-
zone
loss
-
of
-
field
protection
may
be
desirable
.
In
this
case
,
the
Zone
-
1
KLF
impedance
circle
should
be
small
and
fully
offset
in
the
nega
-
tive
reactance
region
.
The
long
-
reach
should
be
set
equal
to
synchronous
reactance
,
Xd
.
The
short
-
reach
should
be
set
equal
to
one
-
half
transient
reactance
,
XDV
2
.
The
trip
cir
-
cuit
should
trip
directly
,
with
no
time
delay
.
The
alarm
circuit
should
operate
a
timer
which
may
be
set
from
14
-
1.0
seconds
,
depending
on
user
preference
.
If
the
con
-
dition
persists
,
this
timer
permits
tripping
.
COMPENSATOR
(
TA
AND
Tc
)
Each
set
of
compensator
taps
terminates
in
in
-
serts
which
are
grouped
on
a
socket
and
form
ap
-
proximately
three
quarters
of
a
circle
around
a
center
insert
which
is
the
common
connection
for
all
the
taps
.
Electrical
connections
between
com
-
mon
insert
and
tap
inserts
are
made
with
a
link
that
is
held
in
place
with
two
connector
screws
,
one
in
the
common
and
one
in
the
tap
.
A
compensator
tap
setting
is
made
by
loosen
-
ing
the
connector
screw
in
the
center
.
Remove
the
connector
screw
in
the
tap
end
of
the
link
,
swing
the
link
around
until
it
is
in
position
over
the
insert
for
the
desired
tap
setting
,
replace
the
connector
screw
to
bind
the
link
to
this
insert
,
and
retighten
the
connector
screw
in
the
center
.
Since
the
link
and
connector
screws
carry
operating
current
,
be
sure
that
the
screws
are
turned
to
bind
snugly
.
The
second
-
zone
KLF
may
be
set
with
a
larger
impedance
characteristic
and
will
detect
partial
loss
-
of
-
field
conditions
.
A
typical
setting
would
be
to
just
allow
the
machine
to
operate
at
maximum
hydrogen
pressure
and
9.5
per
unit
voltage
.
If
a
low
voltage
condition
occurs
,
it
is
recommended
that
tripping
be
accomplished
through
a
timer
set
for
%
second
.
Added
to
the
X
unit
dropout
time
of
‘
4
second
,
this
gives
an
overall
time
of
1.0
second
.
If
the
voltage
is
maintained
,
then
the
alarm
circuit
should
start
a
“
last
-
ditch
”
timer
.
This
timer
may
be
set
anywhere
from
10
seconds
to
one
minute
depending
on
machine
type
and
user
preference
.
Compensator
T
^
requires
an
additional
set
-
ting
for
including
or
excluding
the
origin
of
R
-
X
diagram
from
the
distance
unit
characteristic
.
If
the
desired
characteristic
is
similar
to
that
shown
on
Fig
.
5
b
,
the
links
should
be
set
vertically
in
the
+
T
^
arrow
direction
.
If
a
characteristic
similar
to
that
shown
in
Fig
.
5
c
is
desired
,
set
links
hori
-
zontally
in
the
—
Tc
arrow
direction
.
AUTO
-
TRANSFORMER
PRIMARY
(
SA
AND
Sc
)
PERFORMANCE
DURING
REDUCED
FREQUENCY
Primary
tap
connections
are
made
through
a
single
lead
for
each
transformer
.
The
lead
comes
out
of
the
tap
plate
through
a
small
hole
located
just
below
the
taps
and
is
held
in
place
on
the
proper
tap
by
a
connector
screw
.
During
major
system
break
-
ups
,
it
is
possible
that
the
generators
may
be
called
upon
to
operate
at
reduced
frequency
for
long
periods
of
time
.
During
this
condition
the
loss
-
of
-
field
relay
should
be
secure
and
not
over
-
trip
for
load
conditions
.
The
KLF
relay
has
a
favorable
characteristic
dur
-
ing
this
condition
,
since
its
tripping
characteristic
becomes
more
secure
during
reduced
frequencies
,
as
shown
in
Fig
.
12
.
An
S
setting
is
made
by
removing
the
connec
-
tor
screw
,
placing
the
connector
in
position
over
the
insert
of
the
desired
setting
,
replacing
and
tightening
the
connector
screw
.
The
connector
should
never
make
electrical
contact
with
more
than
one
tap
at
a
time
.
SETTING
THE
RELAY
AUTO
-
TRANSFORMER
SECONDARY
(
MA
AND
MC
)
Secondary
tap
connections
are
made
through
two
leads
identified
as
L
and
R
for
each
transformer
.
These
leads
come
out
of
the
tap
plate
The
type
KLF
relay
requires
a
setting
for
each
of
the
two
compensators
TA
and
TQ
for
each
of
the
two
auto
-
transformers
,
primaries
SA
and
S
^
,
and
for
the
undervoltage
unit
.
13
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
each
through
a
small
hole
,
one
on
each side
of
the
vertical
row
of
M
tap
inserts
.
The
lead
connectors
are
held
in
place
on
the
proper
tap
by
connector
screws
.
DIRECTIONAL
SETTING
There is
not
setting
to
be
made
on
directional
unit
.
INDICATING
CONTRACTOR
SWITCH
(
ICS
)
Values
for
which
an
M
setting
can
be
made
are
from
—
.
15
to
+
.
15
in
steps
of
.
03
.
The
value
of
a
setting
is the
sum
of
the
numbers
that
are
crossed
when
going
from
the
R
lead
position
to
the
L
lead
position
.
The
sign
of
the
M
value
is
determined
by
which
lead
is
in
the
higher
position
on
the
tap
plate
.
The
sign
is
positive
(
+
)
if
the
L
lead
is
higher
and
negative
(
-
)
if
the
R
lead is
higher
.
No
setting
is
required
on
the
ICS
unit
except
the
selection
of
the
0.2
to
2.0
ampere
tap
setting
.
This
selection
is made
by
connecting
the
lead
located
in
front
of
the
tap
block
to
the
desired
set
-
ting
by
means
of
the
connecting
screw
.
When
the
relay
energizes
a
125
volt
or
250
volt
dc
type
WL
relay
switch
,
or
equivalent
,
use
the
0.2
ampere
tap
.
For
48
volt
dc
applications
set
ICS
in
2
ampere
tap
and
use
S
#
304
C
209
G
01
type
WL
relay
coil
or
equivalent
.
An
M
setting
may
be made
in
the
following
manner
:
Remove
the
connector
screws
so
that
the
L
and
R
leads
are
free
.
Determine
from
the
following
table
the desired
M
value
and
tap
positions
.
Neither
lead
connector
should
make
electrical
contact
with
more
than
one
tap
at
a
time
.
INSTALLATION
The
relays
should
be
mounted
on
switchboard
panels
or
their
equivalent
in
a
location
free
from
dirt
,
moisture
,
excessive vibration
,
and
heat
.
Mount
the
relay
vertically
by
means
of
the
four
mounting
holes
on
the
flange
for
semi
-
flush
mounting
or
by
means
of
the
rear
mounting stud
or
studs
for
projection
mounting
.
Either
a
mount
-
ing
stud
or
the
mounting
screws
may
be
utilized
for
grounding
the
relay
.
The electrical
connections
may
be
made
directly
to
the terminals
by
means
of
screws
for
steel
panel
mounting
or
the
terminal
studs
furnished
with the
relay
for
thick
panel
mounting
.
The
terminal studs
may
be
easily
removed
or
inserted
by
locking
two
nuts
on
the
stud and then
turning the
proper
nut
with
a
wrench
.
Tabulated
Settings
L
Lead
Z
T
R
Lead
0.87
TS
0.89
TS
0.92
TS
0.94
TS
0.97
TS
+
.
15
+
.
12
+.
09
+
.
06
+
.
03
Upper
.
06
Upper
.
06
Lower
.
06
Upper
.
06
0
.
03
0
.
03
0
TS
0
0
0
1.03
TS
1.06
TS
1.1
TS
1.14
TS
1.18
TS
-
.
03
-
.
06
-
.
09
-
.
12
-
.
15
0
.
03
Lower
.
06
Upper
.
06
Lower
.
06
Upper
.
06
Upper
.
06
0
.
03
0
For
detailed
FT
Case
information
refer
to
I
.
L
.
41
-
076
.
UNDERVOLTAGE
UNIT
The
voltage
unit is
calibrated
to
close its
con
-
tact
when
the
applied
voltage
is reduced
to
80
volts
.
The
voltage
unit
can
be
set
to
close
its
con
-
tacts
from
70
volts
to
90
volts
by
adjusting
the
resistor located
next
to
the
directional
unit
(
to
the
left
of
the
upper
operating
unit
)
.
The
spiral
spring
is
not
disturbed
when
making
any
setting
other
than
the
calibrated
setting
of
80
volts
.
ADJUSTMENTS
AND
MAINTENANCE
The
proper
adjustments
to
insure
correct
operation
of
this
relay
have
been
made
at
the
fac
-
tory
.
Upon
receipt
of
the
relay
,
no
customer
ad
-
justments
,
other
than
those
covered under
“
SETTINGS
,
”
should
be
required
.
ACCEPTANCE CHECK
The
following
check
is
recommended
to
insure
that
the
relay
is
in
proper
working
order
:
Relay
should
be
energized
for
at
least
one
hour
.
The
undervoltage
unit
range
of
70
to
90
volts
is
equivalent
to
80
to
104
VL
_
L
(
or
67
%
to
87
%
normal
system
voltage
)
.
This is
because the volt
-
age
on
the unit
is
equal
to
1.5
times
VL
-
N
_
14
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
3
.
Raise
the
voltage
to
120
volts
and
vary
the
phase
shifter
to
obtain
the
two
angles
where
the
moving
contact
just
makes
with
the
left
hand
contact
.
These
two
angles
(
where
tor
-
que
reverses
)
should
be
where
the
current
leads
the
voltage
by
283
°
and
103
°
,
±
4
°
.
4
.
Contact
Gap
The
gap
between
the
stationary
contact
and
moving
contact
with
the
re
-
lay
in
deenergized
position
should
be
ap
-
proximately
.
020
”
.
A
.
Distance
Unit
(
Z
)
1
.
Connect
the
relay
as
shown
in
Fig
.
13
with
the
switch
in
position
2
and
the
trip
circuit
deenergized
.
2
.
Make
the
following
tap
settings
:
=
11.5
TA
TC
=
2.55
SA
=
2
SC
=
1
MA
=
.
03
Tc
link
in
middle
block
should
be
set
for
+
TC
direction
.
This
setting
corresponds
to
Z
\
=
23.7
ZQ
=
2.80
Adjust
the
phase
shifter
for
90
°
current
lagging
the
voltage
.
3
.
With
the
terminal
voltage
at
80
volts
,
in
-
crease
current
until
contacts
just
close
.
This
current
should
be
within
±
3
%
of
2.25
amp
(
2.32
-
2.18
amp
.
)
.
This
value
corresponds
to
1.5
Z
\
setting
since
the
voltage
as
applied
to
terminals
4
and
5
is
equivalent
to
1.5
V
JN
voltage
,
or
Mc
=
-
.
09
C
.
Undervoltage
Circuit
1
.
Connect
the
relay
as
shown
in
Fig
.
13
with
switch
in
position
2
and
the
trip
circuit
deenergized
.
2
.
Decrease
the
voltage
until
the
contacts
close
to
the
left
.
This
value
should
be
80
+
3
%
volts
.
D
.
Reactor
Check
Apply
120
volts
AC
across
terminal
6
and
7
.
Measure
voltage
from
terminal
6
to
4
and
7
to
4
.
These
voltages
should
be
equal
to
each
other
with
-
in
+
1
volt
.
V
1
N
80
1
—
x
1.5
2.25
4
.
Adjust
phase
shifter
for
90
°
current
leading
the
voltage
.
5
.
With
the
terminal
voltage
at
80
volts
in
-
crease
current
until
contacts
just
close
.
This
current
should
be
within
+
3
%
of
19.0
amps
.
(
19.6
—
18.4
amps
.
)
This
value
corresponds
1.5
ZC
setting
for
the
same
reason
as
ex
-
plained
above
.
ZA
=
=
23.7
ohms
.
Il
E
.
Telephone
Relay
Apply
rated
dc
volts
across
terminal
10
and
3
.
The
telephone
relay
(
X
)
should
open
its
contact
.
Manually
close
distance
unit
(
Z
)
and
directional
unit
(
D
)
contacts
and
the
X
contact
should
close
.
Routine
Maintenance
All
contacts
should
be
periodically
cleaned
.
A
contact
burnisher
S
#
182
A
836
H
01
is
recommend
-
ed
for
this
purpose
.
The
use
of
abrasive
material
for
cleaning
contacts
is
not
recommended
,
because
of
the
danger
of
embedding
small
par
-
ticles
in
the
face
of
the
soft
silver
and
thus
im
-
pairing
the
contacts
.
Contact
Gap
The
gap
between
the
stationary
con
-
tact
and
moving
contact
with
the
relay
in
deener
-
gized
position
should
be
approximately
.
040
”
.
B
.
Directional
Unit
Circuit
(
D
)
1
.
Connect
the
relay
as
shown
in
Fig
.
13
with
the
switch
in
position
1
and
the
trip
circuit
deenergized
.
2
.
With
a
terminal
voltage
of
1
volt
and
5
am
-
peres
applied
,
turn
the
phase
shifter
to
13
°
(
current
leads
voltage
)
.
The
contacts
should
be
closed
.
This
is
the
maximum
torque
position
.
REPAIR
CALIBRATION
Relay
should
be
energized
for
at
least
one
hour
.
A
.
Auto
-
transformer
Check
Auto
-
transformers
may
be
checked
for
turns
ratio
and
polarity
by
applying
ac
voltage
to
ter
-
minals
4
and
5
and
following
the
procedure
below
.
15
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
1
)
Set
SA
and
Sc
on
tap
number
3
.
Set
the
“
R
”
leads
of
MA
and
Me
all
on
0.0
and
disconnect
the
“
L
”
leads
.
Adjust
the
voltage
for
90
volts
.
Measure
voltage
from
terminal
5
to
the
tap
#
1
of
SA
.
It
should
be
30
volts
(
±
1
)
.
From
terminal
5
to
tap
#
2
of
SA
should
be
60
volts
.
The
same
procedure
should
be
followed
for
taps
#
1
and
#
2
of
S
(
\
2
)
Set
SA
and
Sc
on
1
and
adjust
the
voltage
at
the
relay
terminals
for
100
volts
.
Measure
voltage
drop
from
terminals
5
to
each
of
the
MA
and
Me
taps
.
This
voltage
should
be
equal
to
100
(
±
1
)
plus
the
sum
of
values
between
R
and
tap
being
measured
.
Exam
-
ple
100
(
1
+
.
03
+
.
06
)
=
109
volts
.
Transformers
that
have
an
output
different
from
nominal
by
more
than
1.0
volt
probably
have
been
damaged
and
should
be
replaced
.
moving
contact
1
-
1
/
3
turn
for
a
contact
gap
of
.
040
”
.
2
)
Sensitivity
Adjustment
Using
the
connections
of
Fig
.
13
apply
10
volts
ac
90
°
lagging
,
to
terminals
4
and
5
pass
.
420
amperes
through
current
circuit
(
terminals
9
and
8
)
.
The
spiral
spring
is
to
be
adjusted
such
that
the
contacts
will
just
close
.
Deenergize
the
relay
.
The
moving
contact
should
return
to
open
position
against
the
right
hand
stop
.
C
.
Impedance
Characteristic
Check
1
)
Maximum
Torque
Angle
Adjust
resistor
Rg
(
mounted
on
the
back
of
the
relay
)
to
measure
8800
ohms
.
Applying
100
volts
ac
to
terminals
5
and
4
and
pass
-
ing
5.2
amperes
,
through
the
current
cir
-
cuit
turn
the
phase
shifter
until
the
moving
contact
opens
.
Turn
the
phase
shifter
back
(
few
degrees
)
until
contacts
close
.
Note
de
-
grees
.
Continue
to
turn
the
phase
shifter
until
contact
closes
again
.
Note
degrees
.
The
maximum
torque
angle
should
be
(
±
3
°
)
computed
as
follows
:
Degrees
to
Close
Contacts
at
Left
+
Degrees
to
Close
Contacts
at
Right
B
.
Distance
Unit
(
Middle
Unit
)
Calibration
Make
following
tap
plate
settings
.
TA
=
15.8
;
Tc
=
5.1
SA
=
SC
=
1
Make
MA
=
Me
=
—
.
15
settings
:
“
L
”
lead
should
be
connected
to
the
“
O
”
in
-
sert
.
“
R
”
lead
should
be
connected
to
the
upper
“
.
06
”
insert
.
(
—
.
03
—
.
06.06
=
—
.
15
between
L
&
R
)
.
=
90
°
2
Adjust
resistor
Rg
until
the
correct
maxi
-
mum
-
torque
angle
is
obtained
.
2
)
Impedance
Check
a
.
Adjust
voltage
to
be
90
volts
.
For
current
lagging
90
°
the
impedance
unit
should
close
its
contacts
at
3.12
—
3.35
amp
.
Reverse
current
leads
,
the
impedance
unit
should
close
its
contacts
at
9.7
—
10.3
amperes
.
b
.
Reverse
the
links
in
the
middle
tap
block
to
—
Tc
position
.
Apply
current
of
10
amps
.
The
contacts
should
stay
open
.
Re
-
verse
current
leads
to
original
position
.
The
contacts
should
open
when
current
is
increased
above
9.7
—
10.3
amperes
.
Set
links
back
to
+
TC
position
.
Change
SA
and
Sc
to
setting
“
2
”
.
Keeping
volt
-
For
the
most
accurate
calibration
preheat
re
-
lay
for
at
least
an
hour
by
energizing
terminals
5
,
6
&
7
with
120
volts
,
3
phase
.
The
links
in
the
middle
tap
block
should
be
set
for
the
+
TC
direction
.
1
)
Contact
Gap
Adjustment
The
spring
type
pressure
clamp
holding
the
stationary
contact
in
position
should
not
be
loosened
to
make
the
necessary
gap
adjust
-
ments
.
With
moving
contact
in
the
opened
position
,
i
.
e
.
,
against
right
stop
on
bridge
,
screw
in
stationary
contact
until
both
contacts
just
make
(
use
neon
light
for
indication
)
.
Then
screw
the
stationary
contact
away
from
the
16
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
b
.
Short
circuit
terminals
6
and
7
.
c
.
Screw
in
both
plugs
as
far
as
possible
prior
to
starting
the
adjustment
.
d
.
Apply
80
amps
only
momentarily
,
and
the
directional
unit
need
not
be
cooled
during
initial
rough
adjustment
.
But
,
the
directional
unit
should
be
cool
when
final
adjustment
is
made
.
e
.
When
relay
contact
closes
to
the
left
,
screw
out
the
right
hand
plug
until
spuri
-
ous
torque
is
reversed
.
f
.
When
plug
adjustment
is
completed
check
to
see
that
there
is
no
closing
torque
when
relay
is
energized
with
40
amps
and
volt
-
age
terminals
6
and
7
short
-
circuited
.
4
)
Maximum
Torque
Angle
Check
With
120
volts
and
5
amperes
applied
,
vary
the
phase
shifter
to
obtain
the
two
angles
where
the
moving
contacts
just
close
.
These
two
angles
(
where
torque
reverses
)
should
be
where
the
current
leads
the
voltage
by
283
°
±
4
°
and
105
°
±
2
.
Readjust
the
re
-
actor
Xj
if
necessary
.
age
at
90
volts
,
90
°
lagging
check
pick
-
up
current
.
It
should
be
1.56
—
1.68
amperes
.
Now
set
the
phase
shifter
so
that
voltage
leads
the
current
by
90
°
.
Impedence
unit
should
trip
now
at
4.85
—
5.15
amperes
.
c
.
Set
T
^
=
11.5
,
Tc
=
2.55
,
=
2
,
Sc
=
1
,
MA
=
-
.
03
MC
=
-
.
09
.
Set
volt
-
age
at
90
volts
leading
the
current
by
90
°
.
Impedance
unit
should
trip
at
2.61
—
2.45
amp
.
Reverse
current
leads
.
Pickup
should
be
20.8
—
22.1
amp
.
Change
S
^
,
Sc
=
3
.
Check
pickup
.
It
should
be
6.95
-
7.35
amp
.
Reverse
cur
-
rent
leads
.
Pick
-
up
should
be
now
1.74
—
1.63
amp
.
D
.
Directional
unit
(
Top
Unit
)
1
)
Contact
Gap
Adjustment
The
spring
type
pressure
clamp
holding
the
stationary
contact
in
position
should
not
be
loosened
to
make
the
necessary
gap
adjust
-
ments
.
With
moving
contact
in
the
opened
position
,
i
.
e
.
,
against
right
stop
on
bridge
,
screw
in
stationary
contact
until
both
contacts
just
make
.
Then
screw
the
stationary
contact
away
from
the
moving
contact
3
/
4
of
one
turn
for
a
contact
gap
of
.
022
”
.
2
)
Sensitivity
Adjustment
With
reactor
X
having
its
core
screwed
out
by
about
1
/
8
inch
apply
1.00
volt
to
ter
-
minals
6
and
7
.
Observing
polarities
as
per
schematic
,
and
5
amperes
current
leading
the
voltage
by
13
°
,
the
spiral
spring
is
to
be
adjusted
such
that
the
contacts
will
just
close
.
The
adjustment
of
the
spring
is
ac
-
complished
by
rotating
the
spring
adjuster
which
is
located
on
the
underside
of
the
bridge
.
The
spring
adjuster
has
a
notched
periphery
so
that
a
tool
may
be
used
to
ro
-
tate
it
.
The
spring
type
clamp
holding
the
spring
adjuster
should
not
be
loosened
prior
to
rotating
the
spring
adjuster
.
3
)
Plug
adjustment
for
Reversing
of
Spurious
Torques
a
.
Set
Tc
=
0.0
.
Connect
a
heavy
current
lead
from
T
/
^
center
link
to
terminal
8
.
E
.
Undervoltage
Unit
(
Lower
Unit
)
Note
:
The
moving
contact
is
in
closed
position
to
the
left
when
deenergized
.
1
)
Contact
Gap
Adjustments
a
)
L
.
H
.
(
Normally
Closed
)
Contact
Adjust
-
ment
With
the
moving
contact
arm
in
the
closed
position
,
against
left
hand
side
of
bridge
,
screw
the
left
-
hand
contact
in
to
just
touch
the
moving
contact
(
use
neon
light
for
indication
)
and
then
continue
for
one
more
complete
turn
.
b
)
R
.
H
.
(
Normally
Open
)
Contact
Adjust
-
ment
With
moving
contact
arm
aginst
the
left
hand
stationary
contact
screw
the
right
hand
stationary
contact
until
it
just
touches
the
moving
contact
.
Then
back
the
right
hand
contact
out
two
-
thirds
of
one
turn
to
give
0.020
inch
contact
gap
.
17
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
factory
and
should
not
change
under
normal
con
-
ditions
.
The
mutual
impedance
of
the
compen
-
sators
can
be
checked
with
accurate
instruments
by
the
procedure
outlined
below
.
1
.
Set
TA
on
the
15.8
tap
T
£
on
the
5.1
tap
2
.
Disconnect
the
L
-
leads
of
sections
and
Me
3
.
Pass
10
amperes
ac
current
in
terminal
9
and
out
of
terminal
8
.
4
.
Measure
the
compensator
voltage
with
an
accurate
high
resistance
voltmeter
(
5000
ohms
/
volt
)
.
5
.
Compensator
A
-
voltage
should
be
checked
between
lead
L
^
\
and
terminal
5
.
For
Ty
^
=
15.8
the
voltage
measured
should
be
237
volts
(
+
3
%
)
.
6
.
Compensator
C
voltage
should
be
checked
between
lead
LQ
and
the
fixed
terminal
on
the
resistor
which
is
mounted
in
the
rear
.
For
Tc
=
5.1
,
the
voltage
should
be
76.5
volts
(
+
3
%
)
.
7
.
For
all
other
taps
the
compensator
voltage
is
1.5
IT
(
±
3
%
)
where
I
—
relay
current
T
—
tap
setting
.
1
)
Sensitivity
Adjustment
a
)
Apply
voltage
to
terminals
4
and
5
.
With
the
adjustable
resistor
,
which
is
located
at
the
upper
left
hand
comer
,
set
for
maxi
-
mum
resistance
(
2500
ohms
)
adjust
the
spring
so
that
contacts
make
(
to
the
left
)
at
70
volts
.
The
contacts
should
open
when
unit
is
energized
with
71
or
more
volts
.
b
)
Relay
is
shipped
with
80
volts
setting
.
This
is
accomplished
by
lowering
resist
-
ance
value
until
contacts
make
at
80
volts
and
open
when
unit
is
energized
with
81
or
more
volts
.
The
spring
should
not
be
used
for
this
setting
.
F
.
Indicating
Contactor
Switch
(
ICS
)
Close
the
main
relay
contacts
and
pass
suffi
-
cient
dc
current
through
the
trip
circuit
to
close
the
contacts
of
the
ICS
.
This
value
of
current
should
not
be
greater
than
the
particular
ICS
tap
settings
being
used
.
The
indicator
target
should
drop
freely
.
G
.
Telephone
Relay
Energize
the
telephone
relay
circuit
,
terminals
10
and
3
,
with
rated
dc
voltage
.
The
telephone
relay
(
X
)
should
operate
positively
.
With
an
air
gap
of
.
003
”
-
.
004
”
the
contacts
should
close
in
167
to
250
ms
when
the
telephone
relay
coil
is
shorted
.
This
may
be
done
by
manually
closing
the
distance
unit
(
Z
)
and
directional
unit
(
D
)
contacts
.
RENEWAL
PARTS
Repair
work
can
be
done
most
satisfactorily
at
the
factory
.
However
,
interchangeable
parts
can
be
furnished
to
the
customers
who
are
equipped
for
doing
repair
work
.
When
ordering
parts
,
always
give
the
complete
nameplate
data
.
H
.
Compensator
Check
Accuracy
of
the
mutual
impedance
T
of
the
compensators
is
set
within
very
close
tolerances
at
18
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
POS
.
DC
I
TD
-
I
=
TD
-
A
+
0.25
SEC
.
z
I
0.25
SEC
ID
X
D
/
0
I
1
V
rv
ix
•
ALARM
1
TD
-
2
TD
-
A
TD
-
A
Z
TD
-
2
I
I
10
TRIP
TRIP
0.75
SEC
-
1
MIN
.
SEC
NEG
.
DC
v
TD
-
I
Sub
.
1
3491
A
03
Fig
.
9
.
Generalized
External
Schematic
+
x
R
XD
/
2
XD
-
X
Sub
.
1
3491
A
03
Fig
.
10
.
Zone
-
1
Impedance
Characteristic
.
19
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
748
N
X
R
DIRECTIONAL
ELEMENT
STEADY
STATE
STABILITY
LIMIT
ZONE
2
RELAY
MACHINE
CAPABILITY
CURVE
,
(
MAX
.
H
2
PRESSURE
)
MEL
-
X
Sub
.
1
3491
A
03
Fig
.
11
.
Zone
-
2
impedance
Characteristic
.
X
NOTE
-
FOR
50
HZ
RELAY
ALL
FREQUENCY
VALUES
SHOULD
BE
MULTIPLIED
BY
A
FACTOR
OF
0.8555
HERTZ
R
HERTZ
HERTZ
HERTZ
Sub
.
2
3491
A
08
Fig
.
12
.
KLF
Frequency
Response
for
Impedance
Unit
20
Courtesy of NationalSwitchgear.com