ABB CIRCUIT SHIELD 87T User manual

ABB
IB
7.6
.
1.7
-
4
Issue
B
INSTRUCTIONS
Transformer
Differential
Relay
©
CIRCUIT
&
SHIELD
Catalog
Series
219
Standard
Case
TYPE
87
T
Catalog
Series
419
Drawout
Test
Case
TYPE
87
T
PIFFEBENT
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CAT
TWO
WINDING
RELAY
Courtesy of NationalSwitchgear.com

IB
7.6
.
1.7
-
4
Page
2
Transformer
Differential
Relay
TABLE
OF
CONTENTS
Introduction
Precautions
Placing
Relay
into
Service
App
1
ication
Data
Maintenance
and
Testing
.
..
Page
2
Page
2
Page
2
Page
5
Page
14
INTRODUCTION
These
instructions
contain
the
information
required
to
properly
install
,
operate
,
and
test
the
ABB
Circuit
-
Shield
Type
87
T
single
-
phase
Transformer
Differential
Relay
.
These
mounting
.
the
case
and
clearly
numbered
.
relays
are
housed
in
a
case
suitable
for
conventional
semi
-
flush
panel
All
connections
to
the
relay
are
made
at
terminals
located
on
the
rear
of
Relays
with
catalog
numbers
starting
with
419
are
similar
in
function
to
relays
of
the
earlier
219
series
,
but
offer
totally
drawout
construction
with
integral
test
faci
1
ities
.
and
blade
assembly
upon
removal
of
the
relay
from
its
case
,
are
of
partial
drawout
construction
,
with
the
input
transformers
remaining
in
the
case
upon
withdrawal
of
the
lower
electronic
circuit
board
.
Current
transformer
shorting
is
accomplished
by
a
direct
-
acting
spring
Units
of
the
219
series
PRECAUTIONS
The
following
precautions
should
be
taken
when
applying
these
relays
:
1
.
Incorrect
wiring
may
result
in
damage
,
diagram
before
energizing
,
correct
polarity
.
Be
sure
wiring
agrees
with
the
connection
Be
sure
that
the
dc
control
voltage
is
applied
in
the
2
.
Apply
only
the
rated
dc
control
voltage
marked
on
the
front
panel
.
3
.
Do
not
attempt
to
change
a
current
tap
setting
while
the
relay
is
in
service
.
This
wi
11
likely
cause
the
relay
to
trip
due
to
the
mismatch
created
.
(
Pulling
the
tap
pin
does
not
open
the
ct
circuit
.
)
If
a
control
wiring
insulation
test
is
4
.
High
voltage
tests
are
not
recommended
,
required
,
withdraw
the
unit
from
its
case
before
applying
the
test
voltage
.
5
.
Follow
test
instructions
to
verify
that
the
relay
is
in
proper
working
order
.
CAUTION
:
since
troubleshooting
entails
working
with
energized
equipment
,
care
should
be
taken
to
avoid
personal
shock
.
Only
competant
technicians
familiar
with
good
safety
practices
should
service
these
devices
.
PLACING
THE
RELAY
INTO
SERVICE
1
.
RECEIVING
.
HANDLING
.
STORAGE
Upon
receipt
of
the
relay
(
when
not
included
as
part
of
a
switchboard
)
examine
for
shipping
damage
.
If
damage
or
loss
is
evident
,
file
a
claim
at
once
and
promptly
notify
Asea
Brown
Boveri
.
Use
normal
care
in
handling
to
avoid
mechanical
damage
.
Keep
the
relay
clean
and
dry
.
2
.
INSTALLATION
the
outline
dimensions
and
panel
drilling
are
given
in
Figure
1
.
Mounting
:
Courtesy of NationalSwitchgear.com

Transformer
Differential
Relay
IB
7.6
.
1.7
-
4
Page
3
Connections
:
Typical
connection
diagrams
for
two
and
three
Internal
connections
in
Figure
2
.
winding
transformers
are
shown
in
Figures
3
and
4
.
Special
care
should be taken
to
connect
the dc control
power
in
the
proper
polarity
.
These
relays
have
a
metal front
panel
which is
connected
through
printed
circuit
board
runs
to
a
rear
terminal
marked
"
G
"
.
In
all
applications
this
terminal
should
be
wired
to
ground
.
The
87
T
relay
includes
an
external
resistor which is
supplied
mounted
to
the
case
and
wired
between
terminals
9
and
operation
.
This resistor
must
be connected
for
proper
10
.
Note
:
Connections
are
critical
in
this
application
.
Most
problems
experienced
during
commissioning
are
due
to
incorrect connections
:
interchanged
phases
,
or
ct
polari
-
ties
,
or
incorrect
make
-
up
of
the delta
ct
connections
.
Using
the
transformer
nameplate
drawing
as
the
reference
,
a
phasing
-
check should be made
to
be
sure
that
the
ct
secondary
connections
are
made
up
properly properly
for the
particular
transformer
winding configuration
.
In
case
of
difficulty during
commissioning
,
a
plug
-
in
test
unit is
available
on
loan
from
the
factory
as
an
aid
in
analyzing
connection
problems
;
however
,
significant
load
current
must
be
flowing
to
use
this
device
.
3
.
SETTINGS
Procedures
for
calculating
settings
for
a
particular
installation
are
given
in
the
Application
section
.
CURRENT TAPS
:
The
ct
secondary
currents
seen
by
the
relay
are
usually unequal
due
to
the
primary
to
secondary
ct
’
s
on
the
primary
and
secondary
sides
of
the transformer
.
ratio
of
the
transformer
being
protected
and the
choice
of
ratios
for
the
The
tap
settings
are
selected
to
equalize
the
input
currents
seen
by
the
differ
-
ential
measurement
unit
of
the
relay
.
The
tap
values and
ratios
provided
are
shown
in
Table
1
.
Setting
calculations
will
determine
the
tap
selection
required
for the
high
-
side
and
low
-
side
ct
inputs
.
It
is
important
to
identify
which
input
terminals
of
the
relay
are
connected
to
the
high
-
side
ct
’
s
and
to
the
low
side
ct
’
s
.
these
Then
when
making
settings
,
to
relate
the
front
panel
tap
to
the
input
current
terminals it
affects
:
the left
side
tap
for
input
terminals
1
-
2
,
the
right
side
tap
for
terminals
5
-
6
,
and
the
center
tap
(
on
3
winding
units
)
for
input
terminals
3
-
4
.
%
DIFFERENTIAL
:
The
ABB
Circuit
-
Shield
Type
87
T
relay
operates
when
its
input
currents
differ
in
magnitude
(
vectorial
1
y
)
.
The
operating
point
occurs
when the
difference
,
expressed
as
a
percentage
of the smaller
,
exceeds the
setting
.
The
percentage
differential
or
"
slope
"
setting
is
made
with
the
left
-
hand
front
panel
dial
.
illustrated
in
the
graphs
of
Figures
6
and
7
.
the
operate
current
relative
to
the
tap
value
,
This
continuously adjustable
control allows
settings
from
15
to
40
%
,
and
is
In
these
plots
the
vertical
axis
is
Mo
=
(
Ii
/
T
1
)
-
(
I
2
/
T
2
)
and
the
horizontal
axis is
the
smaller
restraint
current
relative
to
tap
value
MR
=
I
2
/
T
2
The
Percent
Differential is
D
=
MO
/
MR
where
i
nto
and
i
nto
11
is
the
1
arger
restraint
current
T
1
the
tap
value
,
12
is
the smaller
restraint
current
T
2
the
tap
value
.
Note
:
MR
=
R
when
I
2
/
T
2
<
R
where
R
(
adjustable
)
Minimum
Restraint
Courtesy of NationalSwitchgear.com

Transformer
Differential
Relay
IB
7.6
.
1.7
-
4
Page
4
MINIMUM
RESTRAINT
(
Minimum
Operating
Current
)
:
The
minimum
operating
current
is
set
by
the
right
-
hand
dial
on
the
front
panel
,
which
is
continuously
adjustable
.
The
minimum
operating
current
value
is
determined
by
the
following
relationship
between
the
restraint
dial
setting
,
the
percent
differential
setting
,
and
the
current
tap
setting
:
(
D
/
(
100
+
D
)
)
x
R
x
T
Im
D
=
%
differential
setting
R
=
adj
min
restraint
setting
T
=
tap
setting
Im
=
minimum
operating
current
in
amperes
where
For
example
,
with
D
=
25
%
,
R
=
2.3
and
T
=
5
A
:
(
25
/
125
)
x
2.3
x
5
46
%
X
5
A
2.3
A
Im
effect
of
varying
the
Minimum
Restraint
adjustment
is
graphically
illustrated
in
The
Figure
7
and
tabulated
in
this
chart
:
Restraint
Dial
Setting
Minimum
Operate
Current
Percent
Differential
Setting
30
%
of
tap
1
.
05
40
%
1
.
5
43
%
65
%
2.3
21
%
25
%
1
.
05
30
%
1
.
5
45
%
2.3
1
.
05
14
%
15
%
1
.
5
20
%
30
%
2.3
The
setting
that
provides
a
30
-
40
%
minimum
operating
current
would
be
typical
for
most
applications
.
INSTANTANEOUS
:
The
instantaneous
element
operates
directly
on
magnitude
of
the
measured
current
difference
.
This
internal
adjustment
is
factory
set
at
10
x
tap
,
but
may
be
adjusted
from
8
to
20
x
as
may
be
required
by
the
application
.
This
element
must
be
set
by
test
.
Refer
to
the
section
on
Testing
for
the
calibration
procedure
.
HARMONIC
RESTRAINT
:
The
harmonic
restraint
unit
blocks
relay
operation
on
transformer
energization
by
detection
of
the
second
harmonic
content
of
the
inrush
current
.
This
element
is
factory
set
to
restrain
on
15
%
second
harmonic
,
which
is
appropriate
for
most
applications
.
An
internal
calibration
adjustment
provides
a
range
of
approximately
10
-
20
%
,
and
may
be
set
by
test
.
Refer
to
the
section
on
Testing
for
the
calibration
procedure
.
Courtesy of NationalSwitchgear.com

Transformer
Differential
Relay
IB
7.6
.
1.7
-
4
Page
5
APPLICATION
DATA
The
ABB
Circuit
-
Shield
Type
87
T
provides
high
-
speed
differential
protection
for
power
transformers
.
The
Type
87
T
is
a
single
-
phase
relay
.
A
set
of
three
relays
is
required
for
the
pro
-
tection
of
one
power
transformer
.
The
relay
is
offered
in
models
for
the
protection
of
two
winding
and
three
winding
transformers
.
The
relay
has
a
linear
percentage
differential
characteristic
in
order
to
accomodate
ct
ratio
mismatch
,
the
operation
of
on
-
load
tap
changers
,
and
ct
errors
at
high
fault
currents
external
to
the
protected
zone
.
Controls
are
provided
on
the
front
panel
to
adjust
the
slope
(
15
-
40
%
)
,
and
the
minimum
operate
current
.
A
second
-
harmonic
restraint
unit
prevents
relay
operation
on
transformer
magnetizing
inrush
current
.
content
,
but
may
be
adjusted
if
required
.
This
unit
is
factory
calibrated
to
restrain
on
15
%
second
harmonic
An
unrestrained
instantaneous
unit
which
operates
on
the
magnitude
of
the
difference
current
is
provided
to
back
up
the
percentage
differential
unit
.
The
instantaneous
unit
is
factory
set
at
10
x
tap
,
but
may
be
adjusted
(
8
-
20
x
)
in
the
field
.
The
relay
has
ratio
correcting
taps
,
therefore
,
external
auxiliary
ct
’
s
will
not
The
high
continuous
rating
of
each
tap
gives
the
user
more
The
low
burden
of
the
relay
(
see
table
3
)
provides
usually
be
required
,
flexibility
in
selecting
taps
,
improved
ct
performance
.
A
procedure
for
calculating
the
relay
settings
for
a
particular
application
follows
on
page
10
.
MOTE
t
DIMENSIONS
ARE
-
^
5
^
-
MM
8.36
213
6.56
6.66
1.19
175
167
30.2
t
PANEL
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16
o
4.68
3
124
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.
9
*
52.4
i
DRAMfOUT
TEST
CASE
STUD
NUMBERS
(
BACK
VIEW
)
3.19
81.0
6.62
168
Figure
1
:
Relay
Outline
and
Panel
Drilling
Courtesy of NationalSwitchgear.com

IB
7.6
.
1.7
-
4
Page
6
Transformer
Differential
Relay
Specifications
Input
Circuits
:
Ratio
Matching
Taps
:
Continuous
rating
:
1
Second
rating
:
Burden
:
see
Table
1
.
see
Table
2
.
200
Amperes
,
any
tap
.
see
Table
3
.
Percentage
Restraint
Element
:
Minimum
operate
current
:
adjustable
13
-
65
*
of
tap
setting
.
Slope
:
adjustable
15
-
40
*
.
Refer
to
Figures
6
and
7
.
Instantaneous
Element
:
Internally
adjustable
8
-
20
x
tap
.
Factory
set
at
10
x
tap
.
Harmonic
Restraint
Element
:
Restrain
on
2
nd
harmonic
.
Internally
adjustable
approximately
10
*
-
20
*
.
Factory
setting
-
15
*
.
Operating
Time
:
See
Figure
5
.
Output
Contact
Rating
:
@
125
vdc
@
250
vdc
closing
/
tripping
continuous
break
30
A
30
A
5
A
5
A
0.3
A
0.1
A
Operating
Temperature
Range
:
-
20
to
+
70
°
C
models
available
for
125
vdc
@
0.05
A
max
.
drain
110
vdc
@
0.05
A
max
.
drain
250
vdc
@
0.05
A
max
.
drain
220
vdc
@
0.05
A
max
.
drain
48
vdc
@
0.05
A
max
.
drain
32
vdc
and
24
vdc
:
Control
Voltage
:
(
allowable
range
100
-
140
vdc
)
(
allowable
range
88
-
125
vdc
)
(
allowable
range
200
-
280
vdc
)
(
allowable
range
176
-
250
vdc
)
(
allowable
range
38
-
58
vdc
)
see
note
2
below
,
and
page
22
.
TABLE
4
:
CATALOG
NUMBERS
-
COMMON
.
UNITS
Control
Voltage
Catalog
Numbers
Std
Case
Test
Case
System
Freq
.
Type
Windings
87
T
48
vdc
11
Ovdc
125
vdc
250
vdc
Two
60
Hz
.
219
T
2431
219
T
2401
219
T
2441
219
T
2451
419
T
2431
419
T
2401
419
T
2441
419
T
2451
48
vdc
11
Ovdc
125
vdc
220
vdc
50
Hz
.
219
F
2431
219
F
2401
219
F
2441
219
F
2421
419
F
2431
419
F
2401
419
F
2441
419
F
2421
48
vdc
11
Ovdc
125
vdc
87
T
Three
60
Hz
.
219
T
3431
219
T
3401
219
T
3441
419
T
3431
419
T
3401
419
T
3441
50
Hz
.
48
vdc
11
Ovdc
125
vdc
219
F
3431
219
F
3401
219
F
3441
419
F
3431
419
F
3401
419
F
3441
Select
419
series
units
for
new
applications
due
to
the
the
improved
testing
features
.
Notes
:
1
.
2
.
Contact
factory
for
availability
of
units
for
control
voltage
ratings
not
listed
.
Type
96
dc
/
dc
inverter
and
48
vdc
rated
87
T
:
see
page
22
.
For
24
or
32
vdc
control
use
Courtesy of NationalSwitchgear.com

Transformer
Differential
Relay
IB
7.6
.
1.7
-
4
Page
7
Type
87
T
Tap
Ratios
TABLE
1
3.2
4.0
2.9
3.6
4.5
5.0
8.7
2.9
1.00
1.10
1.24
1.38
1
.
72
3.00
1
.
55
3.2
1
.
00
1
.
25
1.13
1
.
41
1.56
2.72
3.6
1
.
00
1.11
1.39
2.42
1
.
25
4.0
1.00
1.13 1.25
2.18
4.5
1.00
1.11
1.93
5.0
1
.
00
1.74
8.7
1.00
Continuous
Current
Ratings
TABLE
2
TABLE
3
Burden
Data
Tap
Setting
Continuous
Rating
Tap
Setting
Ohms
P
.
F
.
2.9
A
3.2
A
3.6
A
4.0
A
4.5
A
5.0
A
8.7
A
1
0
A
2.9
A
3.2
A
3.6
A
4.0
A
4.5
A
5.0
A
8.7
A
0.05
0.05
0.04
0.04
0.04
0.04
0.04
1.0
10
A
1.0
10
A
1.0
1
OA
1
.
0
1
OA
1.0
1
OA
1
.
0
17
A
1.0
Figure
2
:
Internal
Connection
Diagrams
16
D
419
B
Transformer
Differential
Relay
Drawout
Test
Case
Type
87
T
Type
87
T
Transformer
Differential
Relay
Standard
Case
16
D
219
B
++
1
06
O
5
o
3
02
ol
fccJ
fee
?
1
5
a
I
T
T
T
T
G
JT
°
G
r
°
ii
i
i
$
1
E
$
15
OlH
Oja
$
12
$
11
10
?
q
ID
9
*
Notes
:
1
.
Omit
coil
3
-
4
for
two
winding
relays
.
2
.
The
tap
block
associated
with
coil
1
-
2
is
on
left
hand
side
,
when
viewed
from
the
front
of
the
relay
.
3
.
The
tap
block
for
coil
5
-
6
is
on
the
right
hand
side
.
4
.
If
provided
,
the
tap
block
for
coil
3
-
4
is
in
the
center
.
5
.
The
external
resistor
shown
connected
between
terminals
9
and
10
is
supplied
mounted
on
the
relay
and
must
be
in
place
for
proper
operation
.
6
.
The
diode
shown
between
terminals
15
and
16
is
used
for
testing
only
.
See
test
procedures
.
Courtesy of NationalSwitchgear.com

Transformer
Differential
Relay
IB
7.6
.
1.7
-
4
Page
8
Connections
shown
for
Phase
Rotation
a
-
b
-
c
Connections
shown
for
Phase
Rotation
a
-
b
-
c
Delta
-
Wye
Transformer
Delta
-
Delta
Transformer
b
a
c
b
a
c
52
-
1
52
-
1
H
2
r
;
;
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-
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6
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87
T
-
3
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*
87
T
-
2
"
S
4
=
rM
87
T
-
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8
7
8
7
12
11
10
9
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12
11
10
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Control
Power
ft
5
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r
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r
.
86
86
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X
52
-
2
86
52
-
1
a
a
^
86
52
-
1
52
-
2
TC
TC
+
Typical
Connections
for
Differential
Protection
Two
-
Winding
Three
-
Phase
Power
Transformer
Figure
3
:
Note
:
using
the
transformer
nameplate
drawing
as
a
reference
,
a
"
phasing
-
check
"
should
be
made
to
insure
that
the
ct
secondary
connections
are
made
up
properly
for
the
particular
transformer
winding
configuration
.
Courtesy of NationalSwitchgear.com

I
2
3
2
3
H
3
52
-
1
52
-
3
93
!
92
94
3
I
92
94 96
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6
2
94
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,
I
I
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-
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3
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1
±
N
3
!
00
®
I
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®
I
3
45
*
1
9.5
J
3
&
3
o
“
b
~
b
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2
®
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5
(
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YI
3
r
+
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3
93
n
_
p
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0
)
v
:
52
-
2
XI
X
3
+
4
C
IW
=
1
'
87
T
-
2
87
T
-
3
87
T
-
1
[
M
H
8
7
12
1110
9
o
4
W
ovo
12
11
10
9
0
-
4
KJ
OVO
12
11
10 9
y
6
o
+
*
o
D
.
C
.
ff
Sr
r
Control
Power
“
X
xlx
“
i
52
-
3
86
52
-
1
aa
a
^
86
52
-
1
52
-
3
52
-
2
M
2
3
TC
TC TC
CO
-
J
O
)
“
O
*
0
)
CD
•
®
-
J
Figure
4
:
Typical
Connections
for
Differential
Protection
-
Three
-
Winding
Three
-
Phase
Transformer
to
Courtesy of NationalSwitchgear.com

Transformer
Differential
Relay
IB
7.6
.
1.7
-
4
Page
10
CALCULATION
OF
SETTINGS
:
A
procedure
for
calculating
the
relay
settings
follows
,
end
of
the
procedure
.
An
example
is
given
at
the
1
.
Determine
the
maximum
load
currents
of
the
transformer
,
on
the
high
-
side
IH
and
the
1
ow
-
side
II
.
2
.
Determine
the
maximum
through
-
fault
currents
,
IHF
and
ILF
.
3
.
Choose
the
ct
ratio
in
accordance
with
step
1
to
give
approximately
5
A
secondary
current
at
the
maximum
load
current
;
and
,
also
so
that
the
maximum
external
fault
current
is
less
than
100
amperes
secondary
.
others
,
check
that
they
meet
the
requirements
above
.
applications
,
through
-
fault
current
is
limited
by
the
transformer
impedance
.
)
If
the
ct
ratios
have
been
specified
by
(
Note
that
for
2
winding
4
.
Calculate
the
load
currents
on
the
ct
secondary
side
,
IHS
and
ILS
.
remembering
to
multiply
by
for
ct
5
.
Calculate
the
relay
currents
,
IHR
and
ILR
secondaries
connected
in
delta
.
6
.
Calculate
the
ratio
of
the
relay
currents
taking
the
1
arger
/
smal
1
er
A
.
7
.
Referring
to
Table
1
,
choose
the
taps
so
that
the
tap
ratio
(
T
)
is
closest
to
the
relay
current
ratio
(
A
)
.
Properly
assign
the
larger
and
smaller
value
tap
selections
to
the
high
-
side
and
low
-
side
relay
currents
culated
in
step
7
.
in
the
same
manner
as
(
A
)
was
cal
-
if
more
than
one
selection
of
taps
is
available
for
the
tap
ratio
desired
usual
practice
to
choose
tap
values
closest
to
the
normal
relay
currents
IHR
and
ILR
.
I
t
i
s
8
.
Check
that
the
relay
currents
are
within
the
continuous
rating
of
the
relay
refer
to
Table
2
.
|
(
T
-
A
)
/
(
sma
11
er
of
T
or
A
)
|
10
.
Select
the
slope
(
percentage
differential
)
setting
.
Both
the
mismatch
and
transformer
’
s
load
tap
changer
range
must
be
considered
.
S
=
M
+
LTC
.
security
,
the
25
%
setting
should
be
used
for
calculated
slopes
of
15
%
and
below
,
the
40
%
setting
for
calculated
slopes
of
15
-
30
%
.
M
=
Mismatch
9
.
Calculate
the
mismatch
:
the
For
and
11
.
Select
the
Instantaneous
setting
.
This
internal
adjustment
is
factory
set
at
10
x
tap
value
.
The
recommended
setting
is
approximately
10
times
the
power
transformers
self
-
cooled
load
current
rating
:
(
a
)
Calculate
the
relay
current
at
the
transformers
self
-
cooled
rating
.
(
b
)
Divide
by
the
high
-
side
relay
tap
value
.
(
c
)
Multiply
by
1.2
for
margin
.
Set
the
internal
potentiometer
R
119
using
the
calibration
procedures
given
in
the
section
on
Testing
.
The
maximum
burden
presented
to
a
ct
is
given
by
the
12
.
CT
performance
check
:
following
equations
:
2.3
RL
+
RB
+
RA
for
wye
-
connected
ct
’
s
.
3.4
RL
+
3
RB
+
3
RA
for
delta
-
connected
ct
’
s
.
(
this
includes
a
correction
factor
for
the
increased
resistance
of
the
leads
due
to
self
-
heating
effects
)
R
R
RL
is
the
one
-
way
lead
resistance
from
ct
to
the
relay
.
RB
is
the
relay
burden
.
RA
is
the
burden
of
other
devices
in
series
with
the
relay
.
where
(
See
Table
3
)
CT
performance
should
be
satisfactory
if
the
maximum
external
fault
current
flowing
through
R
does
not
require
a
voltage
higher
than
one
-
half
the
ANSI
Class
C
accuracy
rating
of
the
ct
.
Therefore
Vc
>
2
x
RIFS
must
be
satisfied
for
both
the
high
-
side
and
low
-
side
ct
’
s
.
(
Note
:
if
a
multi
-
ratio
ct
is
being
used
,
and
if
the
full
secondary
winding
is
not
being
used
,
then
adjust
the
"
C
"
rating
by
the
factor
NS
/
NT
to
account
for
the
lower
effective
"
C
“
rating
.
(
Ns
=
secondary
turns
used
;
NT
-
total
secondary
turns
.
)
13
.
Minimum
operating
current
:
a
setting
giving
25
-
40
%
minimum
operating
current
would
be
usual
practice
.
See
chart
on
page
4
.
Courtesy of NationalSwitchgear.com