ABB HCB Manual

Instruction
Leaflet
I
.
L
.
41
-
971.2
H
ABB
Power
T
&
D
Company
inc
.
Relay
Division
Coral
Springs
,
FL
33065
A
llll
Type
HCB
Pilot Wire
Relay
System
Effective
April
1987
Supersedes
I
.
L
.
41
-
972.2
G
dated
January
1977
Denotes
change
since
previous
issue
CAUTION
:
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
.
tions
in
the
front
of
the
relay
.
The
R
1
tap
links also
connect
to
the
Rj
resistor
(
looped
resistance
wire
)
.
Ro
consists
of
three
tube
resistors
with
taps
wired
to
the
circularly
arranged
Ro
tap
connections
in
the
front
of
the
relay
.
R
^
taps
are
on
the
R
^
resistance
wire
and
are
wired
to
the
circularly
arranged
R
tap
connections
in
the
front of
the
relay
.
Before
putting
protective
relays
into
APPLICATION
The
type
HCB
relay
is
a
high
speed
pilot
wire
relay
designed
for
the
complete phase
and
ground
protection
of
two
and
three
terminal transmission
lines
.
Simultaneous
tripping
of
the
relay
at
each
ter
-
minal
is
obtained
in
about
20
milliseconds
for
all
faults
.
A
complete
installation
for
a
two
terminal
line consists
of
two
relays
,
two
insulating
trans
-
formers
,
and
an
interconnecting
pilot
wire
circuit
.
For
a
three
terminal
line
,
three
relays
,
three
insul
-
ating
transformers
,
and
a
wye
-
rconnected
pilot
wire
circuit with branches
of
equal
series resistance
are
required
.
SATURATING
TRANSFORMER
The
output
of
the
sequence
filter
connects to
the
primary
of
a
two
-
winding
saturating
transformer
.
The
primary winding
is
tapped
and
wired
to
a
tap
block
T
in
the
front
of
the
relay
.
The
secondary
winding
is
con
-
Q
nected
to
the
zener
clipper
and
from
a
fixed
tap
to
the
relay
coil
circuits
.
POLAR
UNIT
This
unit consists
of
a
rectangular
-
shaped
mag
-
netic
frame
,
an
electromagnet
,
a
permanent
magnet
,
and
an
armature
with
either
one
or
two
contacts
.
The
poles
of
the
cresent
-
shaped
permanent
magnet
bridge
the
magnetic
frame
.
The
magnetic
frame
consists
of
three
pieces
joined
in
the
rear
with
two
brass
rods
and
silver solder
.
These
non
-
magnetic
joints
represent
air
gaps
which
are
bridged
by
two
adjust
-
able
magnetic
shunts
.
The
operating
and
restraint
windings
are
concentrically
wound
around
a
mag
-
netic
core
.
The
armature
is
fastened
to
this
core
at
one
end
and
floats
in
the
front
air
gap
at
the other
end
.
The
moving
contact
is connected
to
the
free
end
of
a
leaf
spring
.
CONSTRUCTION
The
relay
consists
of
a
combination
positive
and
zero
phase
sequence
filter
,
a
saturating
auxiliary
trans
-
former
,
two
full
wave
rectifier
units
,
a
polar
type
relay
O
unit
,
a
zener
clipper
,
and
an
indicating
contactor
switch
(
ICS
)
,
all
mounted
in
a
single
case
.
The
external
equip
-
ment
normally
supplied
with
the
relay
consists
of
an
insulating
transformer
,
a
milliammeter
and
test
switch
.
SEQUENCE
FILTER
The
sequence
filter
consists
of
a
three
-
legged
iron
core
reactor
and
a
set
of
resistors
designated
R
1
and
Ro
.
The
reactor
has
three
windings
;
two
.
primary
and
a
tapped
secondary
winding
,
wound
on
the
center
leg
of
a
"
F
”
type
of
lamination
.
The
secondary
taps
are
wired
to
the
circularly
arranged
R
1
tap
connec
-
RESTRAINT
TAPS
A
set
of
restraint
taps
are
located
on
the
front of
the
relay
near
the
polar
unit
These
taps
are
the
maximum
and minimum
restraint
taps
of
the
relay
.
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
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41
-
971.2
H
INDICATING
CONTACTOR
SWITCH
UNIT
(
ICS
)
mum
of
current
in
the
pilot
wire
.
This
increase
in
operating
current
overcomes
the
restraining
effect
and both
the
relays
operate
.
The
d
-
c
indicating
contactor
switch is
a
small
clapper
-
type
device
.
A
magnetic
armature
,
to
which
leaf
-
spring
mounted
contacts
are
attached
,
is
at
-
tracted
to
the
magnetic
core
upon
energization
of
the
switch
.
When
the switch closes
,
the
moving
contacts
bridge
two
stationary
contacts
,
bypassing
the
main
relay
contacts
.
Also
during
this
operation
,
two
fin
-
gers
on
the
armature
deflect
a
spring
located
on
the
front
of
the
switch
,
which allows the
operation
indi
-
cator
target
to
drop
.
The
target
is
reset
from
the
out
-
side
of
the
case
by
a
push
rod located
at
the
bottom
of
the
cover
.
Within
limits
,
as
defined
in
Figure
7
and
under
Characteristics
/
'
all
the
relays
will
operate
for
an
internal
fault
regardless
of
the fault
current
distribu
-
tion
at
the
various
stations
.
The
nominal
pickup
(
total
internal
fault
current
)
of
the
relaying
system
is
equal
to
the
minimum
trip
of
a
single
relay
multi
-
plied
by
the
number
of
relays
.
For
example
,
if
the
pickup
of
each
relay
,
with
the
pilot
wire
open
,
is
6
amperes
,
a
two
terminal line
system
has
a
nominal
pickup
of
2
x
6
=
12
amperes
.
<
{
The
front
spring
,
in
addition
to
holding
the
target
,
provides
restraint
for
the
armature
,
and
thus
controls
the
pick
-
up
value
of
the
switch
.
PILOT
WIRE
EFFECTS
In
Figure
4
it
can
be
seen
that
a
short
-
circuited
pilot
wire
will
short
circuit
the
relay
operating
coils
.
Depending
on
the
location
of
the
short
,
at
least
one
of
the
relays
will
fail
to
trip
during
an
internal
fault
.
If
the
pilot
wire is
open
circuited
,
almost
all
the
re
-
straint
coil
current
will flow
through
the
operating
coil
and
the
relay
operates
as
an
over
-
current
device
.
OPERATION
The
connection
of
the
HCB
system
of
relays
to
the
protected
transmission line
is
shown
in
Fig
.
8
.
In
such
a
connection
,
the
relays
operate
for
faults
within the
line
terminals but
not
for
faults
external
to
the
protected
transmission
line
.
This
is
accom
-
plished
by
comparing
the relative
polarities
of
vol
-
tages
at
opposite
ends
of
the
transmission
line
by
means
of
a
metallic
pilot
wire
.
Excessive
pilot
wire
series
impedance
will
ap
-
proach
an
open
-
circuited condition
and
the
relays
will
operate
during
external
faults
.
Excessive
pilot
wire
shunt
capacitance
will
approach
a
short
-
circuited
con
-
dition
and the
relays
will
not
operate
.
As
shown
in
Figure
8
,
the
composite
sequence
filter
of
each
HCB
relay
receives
three
phase
current
from
the
current
transformers of
the
transmission line
.
The
composite
sequence
filter
of
the
HCB
converts
the
three
-
phase
current
input
into
a
single
-
phase
voltage
output
,
Vp
,
of
a
magnitude
which
is
an
adjustable
func
-
tion
of
the
phase
A
positive
and
zero
sequence
current
.
This
voltage
,
Vp
,
is
impressed
on
the
primary
wiring
of
the
saturating
transformer
.
The
saturating
transformer
output
voltage
,
V
$
,
is
applied
to
the
relay
coils
and
to
the
pilot
wire
through
an
insulating
transformer
.
The
saturat
-
O
ing
transformer
and
a
zener
clipper
across
its
secondary
winding
serve
to
limit
the
energy
input
to
the
pilot
wire
.
During
an
external fault
,
assuming
matched
relays
,
the
magnitude
ofVg
at
both
stations
will
be the
same
.
The
relative
polarities
of
the
Vg
voltages
will
be
as
shown
in
Figure
4
.
Since
the
voltages
add
,
most
of
the
current
will
circulate
through
the
restraint coils
and
the
pilot
wire
,
with
a
minimum
of
operating
coil
current
.
The
relative
effects of
the
operating
and
re
-
straintcoil
currents
are
such
that
the
relay
is
restrained
.
POLAR
UNIT
THEORY
The
polar
unit
flux
paths
are
shown
in
Figure
5
.
With
balanced
air
gaps
,
the
permanent
magnet
pro
-
duces flux
flowing
in
two
paths
,
one
through
the
front
gaps
and
one
through
the
rear
gaps
.
This
flux
produces
north
and south
poles
,
as
shown
.
By
turning
the left
shunt
in
,
some
of
the
flux
is
forced
through
the
armature
,
making
it
a
north
pole
.
Thus
,
reducing
the left
-
hand
rear
gap
will
produce
a
force
tending
to
pull
the
armature
to
the
right
.
Similarly
,
reducing
the
right
-
hand
gap
will
produce
a
force
tending
to
pull
the
armature
to
the left
.
CHARACTERISTICS
The
voltage
,
Vp
,
impressed
by
the filter
upon
the
saturating
transformer
is
:
Vp
=
R
i
+
^
AO
(
^
1
volts
where
Rj
and
R
0
are
the
positive
and
zero
sequence
tap
values
,
respectively
;
(
1
)
During
an
internal
fault
,
the
relative
Vg
polarities
reverse
.
Since
the
Vg
voltages
now
oppose
each
other
,
most
of
the
current
flowing
in
the
restraint
coils is
also
forced
through
the
operating
coils with
a
mini
-
I
^
i
and
IAO
are
the
Positive
and
zero
sequence
phase
A
current
inputs
,
respectively
,
in
amperes
.
These
are
vector
quantities
.
2
Courtesy of NationalSwitchgear.com

I
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41
-
971.2
H
O
Fig
.
7
-
Type
HCB
Relay
Without
Case
(
Front
View
)
.
3
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
971.2
H
O
F
ig
.
2
.
Type
HCB
Relay
Without
Case
(
Rear View
)
.
4
Courtesy of NationalSwitchgear.com

I
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L
.
41
-
971.2
H
NOMINAL
PICKUP
(
ALL
RELAYS
)
SINGLE
RELAY
PICKUP
(
PILOT
WIRE
OPEN
)
ls
,
is
defined
as
Single relay
pickup
,
Is
,
is
defined
as
the
phase
current
required
to
operate
one
relay
with
the
pilot
wire
side
of
the
insulating
transformer
open
circuited
(
H
1
-
H
4
)
.
The
single relay
pickup point
in
terms
of
filter
voltage
is
:
The
nominal
pickup
,
I
nom
(
6
)
I
=
KIS
nom
=
total internal
fault
current
K
=
number
of
relays
(
2
or
3
)
Is
=
single
-
relay
pickup
with
pilot
wire
disconnected
(
see
above
)
where
I
nom
VF
=
0.2
T
(
2
)
where
T
is
the
saturating
transformer
tap
value
.
Single relay
pickup
is
defined
by
equating
(
1
)
&
(
2
)
:
For
example
,
for
a
phase
-
A
-
to
-
ground
fault
,
I
^
i
11
IAO
with
the
pilot
wire
open
circuited
,
the
single
-
relay
pickup
was
previously
determined
as
IAG
"
0.471
am
-
pere
.
For
a
two
-
terminal
line
,
the
nominal
pickup
for
a
phase
-
A
-
to
-
ground
fault
(
Rj
=
0.1
;
Ro
-
1.6
;
T
=
4
)
0.2
T
—
2
i
Rj
+
IAQ
(
^
1
3
R
0
)
(
3
)
Current
Is
varies
with the
type
of
fault
.
For
ex
-
ample
,
for
a
3
phase
fault
,
Is
=
IA
1
,
since
only
posi
-
tive
sequence
currentis
present
.
Substituting
Is
=
IAI
in
Eq
.
(
3
)
&
rearranging
,
the
3
phase
fault
pickup
is
:
is
:
(
A
to
G
)
-
0.471
K
=
0.471
x
2
=
0.942
ampere
.
I
nom
-
— —
(
3
phase
fault
) (
4
)
IS
=
IAI
=
MINIMUM
TRIP
(
ALL
RELAYS
)
2
Ri
IORI
With
equal
inputs
to
all
relays
and
zero
pilot
-
wire
shunt
capacitance
,
the
relays
will
operate
at
their
nominal
pick
-
up
point
.
The
minimum
trip
points
will
vary
somewhat
from
nominal
value
,
depending
on
the
pilot
-
wire
constants
and
the
magnitude
and
phase
angle
of
the
various
relay
input
currents
.
For
exam
-
ple
,
Figure
6
shows
the
relay operating
points
for
a
two
-
terminal line
,
assuming
input
current
to
the
near
relay only
.
If
Rx
=
0.1
,
R
0
=
1.6
&
T
=
4
:
I
-
T
S
IORi
10
X
0.1
i
—
=
4
amp
.
(
3
phase
fault
)
For
a
phase
A
to
ground
fault
,
if
I
A
I
-
IA
2
"
*
A
0
(
IA
2
is
^
e
phase
A
negative
sequence
current
)
:
0.2
T
=
2
IA
1
Rl
+
IA
1
(
Rl
+
3
R
0
)
An
example
of
the characteristics
with
various
current
distributions is shown
in
Figure
7
.
The
filter
output
voltage
,
VF
,
of
each
relay
,
as
defined
by
equation
(
1
)
must
be
in
phase
or
180
degrees
out
of
phase
,
in
order
for
Figure
7
to
apply
.
0.2
T
-
!
A
0
lAl
~
3
(
Rj
+
R
0
)
But
:
Is
-
IA
1
+
IA
2
+
IA
0
=
31
A
i
INSULATING
TRANSFORMER
0.2
T
(
A
-
G
fault
)
(
5
)
So
:
Is
=
3
IA
1
=
Unless
otherwise
noted
,
all
characteristics
pre
-
sented
include
an
insulating
transformer
with
each
relay
.
Two
ratios
are
available
:
4
/
1
and
6
/
1
.
The
high
voltage
side
is
connected
to
the
pilot
-
wires
.
Rl
+
RQ
Rl
=
0.1
,
R
0
=
1.6
&
T
=
4
:
If
0.2
x
4
0.2
T
h
=
Rl
+
RQ
0.1
+
1.6
0.8
=
0.471
amp
.
(
A
-
G
fault
)
"
1.7
5
Courtesy of NationalSwitchgear.com

I
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.
41
-
971.2
H
INTERNAL
SCHEMATIC
14
16
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JACK
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8
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.
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v
-
J
TERMINAL
FRONT
VIE
\
y
A
B
N
C
Sub
5
629
A
312
O
F
9
-
3
-
Internal
Schematic
of
the
Type
HCB
Relay
in
FT
’
42
Case
(
Double
Trip
Circuit
)
.
For
the
Single
Trip
Relay
the
Circuits
Associated with
Terminal
II
are
omitted
.
6
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
971.2
H
INSULATING
TRANSFORMER
SATURATING
TRANSFORMER
TH
*
)
SATURATING
TRANSFORMER
PILOT
N
N
R
A
k
FILTER
FILTER
OP
OP
B
B
C
c
WIRE
R
-
RESTRAINT
COIL
OP
-
OPERATING
COIL
vs
-
SATURATING
TRANSFORMER
VOLTAGE
OUTPUT
(
REEATIVE
POLARITIES
ARE
FOR
THRU
CURRENT
OR
EXTERNAL
FAULT
)
183
A
061
Fig
.
4
.
Simplified
External
Schematic
of
the
HCB
Belay
System
.
SHUNT
X
-
I
i
t
PERMANENT
MAGNET
t
:
x
:
h
rT
"
l
XX
)
ARMATuRE
ADDITIONAL
FLUX
PATH
Mllfs
S
*
N
Cl
^
N
i
MOVINu
CONTACT
UNBALANCED
AIR
CAPS
BALANCED
AIR
JAPS
183
A
062
Fig
.
5
.
Polar
Unit
Permanent
Magnet
Flux
Paths
.
PILOT
-
WIRE
REQUIREMENTS
TABLE
I
The
relays
should
not
be
applied
with
pilot
-
wire
series
resistance
or
shunt
capacitance
exceeding
the
following
values
:
Insulating
Transformer
Ratio
No
.
of
Relays
6
/
1
4
/
1
RL
Cs
RL
Cs
2000
50
°
/
LEG
]
.
5
2
1000
/
LEG
0.75
1.8
3
RL
=
series
loop
resistance
in
ohms
.
Cs
=
total
shunt
capacitance
in
microfarads
.
7
Courtesy of NationalSwitchgear.com

I
.
L
.
41
-
971.2
H
close
to
the
remote
ground
potential
in
the
presence
of
a
rise
in
station
-
ground
potential
.
They
do
not
limit
pilot
-
wire
voltages
to
safe
values
in
the
presence
of
a
longitudinal
induced
voltage
.
When
using
the
neutralizing
reactor
,
the
pilot
-
wire
sheath
should
be
insulated
from
station
ground
to
minimize
sheath
-
to
-
pair potential
in
the
presence
of
a
rise
in
station
-
ground
potential
.
All
other
pairs
in
the
cable
which
are
connected
to
station
ground
should also
be
pro
-
tected
with
neutralizing
reactors to
minimize
pair
-
to
-
pair
voltages
.
b
)
Drainage
reactors
may
be
connected
across
the
pilot
wire
and
to
ground through
a
KX
642
protector
tube
.
The
drainage
reactor
is
particularly
effective
in
limiting
pair
-
to
-
ground
voltage
in
the
presence
of
an
induced
voltage
.
When
the
tube
flashes
,
both
wires
are
connected
to
ground
through
the
drainage
reactor
windings
which
offer
a
low
impedance
to
ground
but
maintain
a
high
impedance
to
an a
-
c
voltage
across
the
wires
.
Thus
,
the
HCB
system
will
operate
normally
even
though
the
protector
tube
has flashed
over
.
The
drainage
reactor
is
not
intended
to
handle
a
rise
in
ground
potential
.
619594
Fig
.
6
.
Typical
Curves
Showing
the
Effect of
the
Pilot
Wire
on
Minimum
Trip
Current
,
Two
-
Terminal
Line
(
Maximum
Restraint
Tap
)
.
Insulating
Transformer
4
/
1
Ratio
.
Where
the
shunt
capacitance
exceeds
the
above
amount
,
it
may
be
feasible
in
some cases
to
provide
shunt
reactors to
compensate
for
the
excessive
ca
-
pacitance
.
The
amount
of
capacitance
which
can
be
compensated
is
limited and
varies
depending
upon
the
magnitude
of
the
pilot
-
wire
distributed
effect
.
c
)
The
neutralizing
and
drainage
reactors
may
be utilized
together
.
If
the
neutralizing
reactor
is
to
be
of
any
value
,
the
drainage
reactor
through
the
KX
642
pro
-
tector
tube
must
be connected
to
remote
ground
.
For
information with
reference
to
the
insula
-
tion and
protection
equipment
,
refer
to
I
.
L
.
41
-
971.4
.
A
shielded
,
twisted
pilot
wire
pair
,
preferably
of
#
19
AWG
or
larger
,
is
recommended
;
however
,
open
wires
may
be used
if
they
are
frequently
transposed
in
areas
of
exposure
to
power
circuit
induction
.
The
voltage
impressed
across
either
insulating
transformer
(
H
-
l
to
H
-
4
)
as
a
result
of
induction
or
a
rise
in
sta
-
tion
ground
potential
,
should
be
less
than
7.5
volts
to
prevent
undesired
relay
operation
.
TRIP
CIRCUIT
The
main
contacts
will
safely
close
30
amperes
at
250
volts d
.
c
.
,
and
the seal
-
in
contacts
of
the
in
-
dicating
contactor
switch
will
safely
carry
this
cur
-
rent
long enough
to
trip
a
circuit breaker
.
The
indicating
contactor
switch has
two
taps
that
provide
a
pick
-
up
setting
of
0.2
or
2
amperes
.
To
change
taps
requires
connecting
the lead
located
in
front of
the
tap
block
to
the
desired
setting
by
means
of
a
screw
connection
.
For
three
-
terminal
applications
,
the
loop
resist
-
ance
of
all
legs
of
the
pilot
wire
must
be
balanced
within
5
percent
,
with variable resistors
as
shown
in
Figure
8
.
The
pilot
wire
resistance
to
be balanced
is
divided
by
16
and
36
for
the
4
to
1
and
6
to
1
ratio
insulating
transformers
respectively
,
since the
bal
-
ancing
resistors
are
located
on
the
relay
side
of
the
insulating
transformers
.
SETTINGS
There
are
four
settings
in
the
relay
.
The
correct
tap
setting
should be
determined
as
outlined
under
Setting
Calculations
”
.
1
)
Restraint
taps
-
maximum
or
minimum
To
change
taps
,
connect
the
lead
in
front
of
the
relay
to
the
correct
tap
.
Induced
voltages
and
rises
in
station
-
ground
po
-
tential
may
be handled
by
the
following
means
:
1 1
a
)
Neutralizing
reactors
may
be
connected
in
series
with the
pilot
wire
to
hold
the
pilot
wire
potential
8
Courtesy of NationalSwitchgear.com

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-
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the
Type
HCB
Relay
in
FT
-
42
Case
•
Two
-
or
Three
-
Terminal
Line
.
O
Fig
.
8
.
10
Courtesy of NationalSwitchgear.com