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